You are an expert Python programmer. Write correct, efficient Python 3 code that solves the problem and passes all tests. Output the code in the following format: ```python
<code>
```

PROBLEM:
You are given an array of integers nums. You must repeatedly perform one of the following operations while the array has more than two elements:

Remove the first two elements.
Remove the last two elements.
Remove the first and last element.

For each operation, add the sum of the removed elements to your total score.
Return the maximum possible score you can achieve.

Example 1:

Input: nums = [2,4,1]
Output: 6
Explanation:
The possible operations are:

Remove the first two elements (2 + 4) = 6. The remaining array is [1].
Remove the last two elements (4 + 1) = 5. The remaining array is [2].
Remove the first and last elements (2 + 1) = 3. The remaining array is [4].

The maximum score is obtained by removing the first two elements, resulting in a final score of 6.

Example 2:

Input: nums = [5,-1,4,2]
Output: 7
Explanation:
The possible operations are:

Remove the first and last elements (5 + 2) = 7. The remaining array is [-1, 4].
Remove the first two elements (5 + -1) = 4. The remaining array is [4, 2].
Remove the last two elements (4 + 2) = 6. The remaining array is [5, -1].

The maximum score is obtained by removing the first and last elements, resulting in a total score of 7.

Constraints:

1 <= nums.length <= 105
-104 <= nums[i] <= 104

Your solution to the problem should be a method of the class Solution called maxScore and should pass all tests. Use the following starter code:
```python
class Solution:
    def maxScore(self, nums: List[int]) -> int:
        # Add your code here
```

SOLUTION:

Question:
PROBLEM:
You are given an array of integers nums. You must repeatedly perform one of the following operations while the array has more than two elements:

Remove the first two elements.
Remove the last two elements.
Remove the first and last element.

For each operation, add the sum of the removed elements to your total score.
Return the maximum possible score you can achieve.

Example 1:

Input: nums = [2,4,1]
Output: 6
Explanation:
The possible operations are:

Remove the first two elements (2 + 4) = 6. The remaining array is [1].
Remove the last two elements (4 + 1) = 5. The remaining array is [2].
Remove the first and last elements (2 + 1) = 3. The remaining array is [4].

The maximum score is obtained by removing the first two elements, resulting in a final score of 6.

Example 2:

Input: nums = [5,-1,4,2]
Output: 7
Explanation:
The possible operations are:

Remove the first and last elements (5 + 2) = 7. The remaining array is [-1, 4].
Remove the first two elements (5 + -1) = 4. The remaining array is [4, 2].
Remove the last two elements (4 + 2) = 6. The remaining array is [5, -1].

The maximum score is obtained by removing the first and last elements, resulting in a total score of 7.

Constraints:

1 <= nums.length <= 105
-104 <= nums[i] <= 104

Your solution to the problem should be a method of the class Solution called maxScore and should pass all tests. Use the following starter code:
```python
class Solution:
    def maxScore(self, nums: List[int]) -> int:
        # Add your code here
```

SOLUTION:

assert Solution().maxScore(nums = [5,-1,4,2]) == 7

assert Solution().maxScore(nums = [1, 2, 3]) == 5

assert Solution().maxScore(nums = [1]) == 0

assert Solution().maxScore(nums = [-5,5,-5,5,-5,5]) == 0

assert Solution().maxScore(nums = [1, 2]) == 0

assert Solution().maxScore(nums = [2,4,1]) == 6

assert Solution().maxScore(nums = [1,2,3,4,5]) == 14

assert Solution().maxScore(nums = [1,2]) == 0

assert Solution().maxScore(nums = [0, 0, 0, 0, 0]) == 0

assert Solution().maxScore(nums = [1, -1, 2, -2, 3, -3]) == 0

assert Solution().maxScore(nums = [1,2,3]) == 5

assert Solution().maxScore(nums = [-1, 2, -3, 4, -5, 6]) == 4

assert Solution().maxScore(nums = [3, 1, 2, 4, 5, 6]) == 18

Answer: assert Solution().maxScore(nums = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1]) == 8

Answer: assert Solution().maxScore(nums = [5,-1,4,2]) == 7

Answer: assert Solution().maxScore(nums = [10000,-10000,10000,-10000,10000]) == 20000

Answer: assert Solution().maxScore(nums = [1, 2, 3]) == 5

Answer: assert Solution().maxScore(nums = [10,9,8,7,6,5,4,3,2,1]) == 52

Answer: assert Solution().maxScore(nums = [1,2,3,4,5,6,7,8,9,10]) == 52

Answer: assert Solution().maxScore(nums = [1]) == 0

Answer: assert Solution().maxScore(nums = [-5,5,-5,5,-5,5]) == 0

Answer: assert Solution().maxScore(nums = [1, 2]) == 0

Answer: assert Solution().maxScore(nums = [10, -10, 20, -20, 30, -30, 40, -40, 50]) == 90

Answer: assert Solution().maxScore(nums = [5,1,5,1,5,1,5,1,5,1]) == 24

Answer: assert Solution().maxScore(nums = [2,4,1]) == 6

Answer: assert Solution().maxScore(nums = [-1,-2,-3,-4,-5]) == -10

Answer: assert Solution().maxScore(nums = [-5,-4,-3,-2,-1]) == -10

Answer: assert Solution().maxScore(nums = [1,-1,1,-1,1,-1,1,-1,1,-1]) == 0

Answer: assert Solution().maxScore(nums = [10000, -10000, 10000, -10000, 10000]) == 20000

Answer: assert Solution().maxScore(nums = [1,2,3,4,5]) == 14

Answer: assert Solution().maxScore(nums = [1,1,1,1,1,1,1,1,1,1]) == 8

Answer: assert Solution().maxScore(nums = [10, -10, 20, -20, 30]) == 50

Answer: assert Solution().maxScore(nums = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]) == 0

Answer: assert Solution().maxScore(nums = [100, -50, 200, -300, 400, -500, 600, -700, 800, -900]) == -250

Answer: assert Solution().maxScore(nums = [1,2]) == 0

Answer: assert Solution().maxScore(nums = [0, 0, 0, 0, 0]) == 0

Answer: assert Solution().maxScore(nums = [1, -1, 2, -2, 3, -3]) == 0

Answer: assert Solution().maxScore(nums = [1,2,3]) == 5

Answer: assert Solution().maxScore(nums = [29, 27, 25, 23, 21, 19, 17, 15, 13, 11, 9, 7, 5, 3, 1]) == 224

Answer: assert Solution().maxScore(nums = [1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31]) == 252

Answer: assert Solution().maxScore(nums = [100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110]) == 1055

Answer: assert Solution().maxScore(nums = [100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500]) == 11900

Answer: assert Solution().maxScore(nums = [10, -10, 20, -20, 30, -30, 40, -40, 50, -50, 60, -60, 70, -70, 80, -80, 90, -90, 100, -100]) == 0

Answer: assert Solution().maxScore(nums = [-1, -2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -13, -14, -15, -16, -17, -18, -19, -20]) == -171

Answer: assert Solution().maxScore(nums = [100, 200, 300, 400, 500, 600, 700, 800, 900, 1000]) == 5200

Answer: assert Solution().maxScore(nums = [100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100]) == 9900

Answer: assert Solution().maxScore(nums = [0, 1, 0, -1, 0, 2, 0, -2, 0, 3, 0, -3, 0, 4, 0, -4, 0, 5, 0, -5]) == 5

Answer: assert Solution().maxScore(nums = [1000, -1000, 500, -500, 250, -250, 125, -125, 62, -62]) == 500

Answer: assert Solution().maxScore(nums = [1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29]) == 224

Answer: assert Solution().maxScore(nums = [5, -5, 5, -5, 5, -5, 5, -5, 5, -5]) == 0

Answer: assert Solution().maxScore(nums = [100, -100, 200, -200, 300, -300, 400, -400, 500, -500]) == 0

Answer: assert Solution().maxScore(nums = [100, 100, -50, -50, 200, -300, 400, -500, 600, -700]) == -100

Answer: assert Solution().maxScore(nums = [1, -2, 3, -4, 5, -6, 7, -8, 9, -10, 11, -12, 13, -14, 15, -16, 17, -18, 19, -20]) == -9

Answer: assert Solution().maxScore(nums = [100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000]) == 20700

Answer: assert Solution().maxScore(nums = [10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130]) == 900

Answer: assert Solution().maxScore(nums = [99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110]) == 1055

Answer: assert Solution().maxScore(nums = [-1, -3, -5, -7, -9, -11, -13, -15, -17, -19]) == -64

Answer: assert Solution().maxScore(nums = [3, 1, -2, 5, 7, -10, 15]) == 29

Answer: assert Solution().maxScore(nums = [-10, -20, -30, -40, -50, -60, -70, -80, -90, -100, -110, -120, -130]) == -780

Answer: assert Solution().maxScore(nums = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]) == 28

Answer: assert Solution().maxScore(nums = [1, 1000000, 1, 1000000, 1, 1000000, 1, 1000000, 1, 1000000, 1, 1000000]) == 5000005

Answer: assert Solution().maxScore(nums = [1, 3, 2, 5, 4, 7, 6, 9, 8, 11, 10]) == 65

Answer: assert Solution().maxScore(nums = [10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10]) == 990

Answer: assert Solution().maxScore(nums = [10, -20, 30, -40, 50, -60, 70]) == 100

Answer: assert Solution().maxScore(nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]) == 324

Answer: assert Solution().maxScore(nums = [1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000, 1, 2, 3, 4, 5]) == 1111111125

Answer: assert Solution().maxScore(nums = [-10, 100, -20, 200, -30, 300, -40, 400]) == 820

Answer: assert Solution().maxScore(nums = [5, 4, 3, 2, 1, 0, 1, 2, 3, 4, 5]) == 30

Answer: assert Solution().maxScore(nums = [1000, -1000, 2000, -2000, 3000, -3000, 4000, -4000, 5000, -5000]) == 0

Answer: assert Solution().maxScore(nums = [5, 1, 3, 7, 9, 2, 6, 4, 8, 10, 12, 14]) == 77

Answer: assert Solution().maxScore(nums = [5, 3, 8, 1, 9, 4, 7, 6, 2, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]) == 202

Answer: assert Solution().maxScore(nums = [10, 9, 8, 7, 6, 5, 4, 3, 2, 1]) == 52

Answer: assert Solution().maxScore(nums = [1, -1, 2, -2, 3, -3, 4, -4, 5, -5, 6, -6, 7, -7, 8, -8, 9, -9, 10, -10]) == 0

Answer: assert Solution().maxScore(nums = [1, 3, 5, 7, 9, 11, 13, 15, 17, 19]) == 96

Answer: assert Solution().maxScore(nums = [-1, -3, -5, -7, -9, -11, -13, -15, -17, -19, -21, -23, -25, -27, -29]) == -196

Answer: assert Solution().maxScore(nums = [-10, -20, -30, -40, -50, -60, -70, -80, -90, -100, -110]) == -550

Answer: assert Solution().maxScore(nums = [1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1]) == 2

Answer: assert Solution().maxScore(nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]) == 119

Answer: assert Solution().maxScore(nums = [100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, -500, -400, -300, -200, -100]) == 4500

Answer: assert Solution().maxScore(nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]) == 52

Answer: assert Solution().maxScore(nums = [1, -2, 3, -4, 5, -6, 7, -8, 9, -10]) == -4

Answer: assert Solution().maxScore(nums = [-1, 2, -3, 4, -5, 6]) == 4

Answer: assert Solution().maxScore(nums = [10000, -10000, 10000, -10000, 10000, -10000]) == 0

Answer: assert Solution().maxScore(nums = [100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100]) == 6500

Answer: assert Solution().maxScore(nums = [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]) == 43

Answer: assert Solution().maxScore(nums = [1, 3, 2, 5, 4, 7, 6, 9, 8, 11, 10, 13, 12, 15, 14]) == 119

Answer: assert Solution().maxScore(nums = [-100, -200, 300, 400, -500, 600]) == 800

Answer: assert Solution().maxScore(nums = [10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120]) == 750

Answer: assert Solution().maxScore(nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]) == 207

Answer: assert Solution().maxScore(nums = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]) == 119

Answer: assert Solution().maxScore(nums = [-10, -9, -8, -7, -6, -5, -4, -3, -2, -1]) == -36

Answer: assert Solution().maxScore(nums = [1000, -999, 888, -777, 666, -555, 444, -333, 222, -111]) == 556

Answer: assert Solution().maxScore(nums = [10, -20, 30, -40, 50, -60, 70, -80, 90, -100]) == -40

Answer: assert Solution().maxScore(nums = [1, 3, 5, 7, 9, 11, 13]) == 48

Answer: assert Solution().maxScore(nums = [3, 1, 2, 4, 5, 6]) == 18

Answer: assert Solution().maxScore(nums = [-1, 1, -2, 2, -3, 3, -4, 4, -5, 5, -6, 6, -7, 7, -8, 8, -9, 9, -10, 10]) == 1

Answer: assert Solution().maxScore(nums = [5, 4, 3, 2, 1, 0, -1, -2, -3, -4, -5]) == 5

Answer: assert Solution().maxScore(nums = [-1, 2, -3, 4, -5, 6, -7, 8, -9, 10]) == 6

Answer: assert Solution().maxScore(nums = [5, 3, 8, 2, 4, 7, 1, 6, 9, 0]) == 39

Answer: assert Solution().maxScore(nums = [-100, -101, -102, -103, -104, -105, -106, -107, -108, -109, -110]) == -1045

Answer: assert Solution().maxScore(nums = [-1, -2, -3, -4, -5, -6, -7, -8, -9, -10]) == -36

Answer: assert Solution().maxScore(nums = [1, -1, 2, -2, 3, -3, 4, -4, 5, -5]) == 0

Answer: assert Solution().maxScore(nums = [10, 20, 30, 40, 50, 60, 70, 80, 90, 100]) == 520

Answer: assert Solution().maxScore(nums = [5, -1, 4, 2, 3, 6, -2, 8, -3, 7]) == 26

Answer: assert Solution().maxScore(nums = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]) == 18

Answer: assert Solution().maxScore(nums = [1, -1, 1, -1, 1, -1, 1, -1, 1, -1]) == 0

Answer: assert Solution().maxScore(nums = [-1000, 2000, -3000, 4000, -5000, 6000, -7000, 8000, -9000, 10000]) == 6000

Answer: assert Solution().maxScore(nums = [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]) == 44

Answer: assert Solution().maxScore(nums = [5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5]) == 70

Answer: assert Solution().maxScore(nums = [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]) == 231

Answer: assert Solution().maxScore(nums = [1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1]) == 0

Answer: assert Solution().maxScore(nums = [100, -50, 25, -10, 15, 20, -30]) == 120

Answer: assert Solution().maxScore(nums = [0, 10000, -10000, 10000, -10000, 0, 10000, -10000, 10000, -10000]) == 10000

Answer: assert Solution().maxScore(nums = [1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000]) == 52000

import random
import functools
import collections
import string
import math
import datetime

from typing import *
from functools import *
from collections import *
from itertools import *
from heapq import *
from bisect import *
from string import *
from operator import *
from math import *

inf = float('inf')

class ListNode:
    def __init__(self, val=0, next=None):
        self.val = val
        self.next = next

def list_node(values: list):
    if not values:
        return None
    head = ListNode(values[0])
    p = head
    for val in values[1:]:
        node = ListNode(val)
        p.next = node
        p = node
    return head

def is_same_list(p1, p2):
    if p1 is None and p2 is None:
        return True
    if not p1 or not p2:
        return False
    return p1.val == p2.val and is_same_list(p1.next, p2.next)

class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right

def tree_node(values: list):
    if not values:
        return None
    root = TreeNode(values[0])
    i = 1
    queue = deque()
    queue.append(root)
    while queue:
        node = queue.popleft()
        if i < len(values) and values[i] is not None:
            node.left = TreeNode(values[i])
            queue.append(node.left)
        i += 1
        if i < len(values) and values[i] is not None:
            node.right = TreeNode(values[i])
            queue.append(node.right)
        i += 1
    return root

def is_same_tree(p, q):
    if not p and not q:
        return True
    elif not p or not q:
        return False
    elif p.val != q.val:
        return False
    else:
        return is_same_tree(p.left, q.left) and is_same_tree(p.right, q.right)

class Solution:
    def maxScore(self, nums: List[int]) -> int:
        s = sum(nums)
        if len(nums) & 1:
            return s - min(nums)
        return s - min(a + b for a, b in pairwise(nums))


You are an expert Python programmer. Write correct, efficient Python 3 code that solves the problem and passes all tests. Output the code in the following format: ```python
<code>
```

PROBLEM:
You are given a binary string s of length n, where:

'1' represents an active section.
'0' represents an inactive section.

You can perform at most one trade to maximize the number of active sections in s. In a trade, you:

Convert a contiguous block of '1's that is surrounded by '0's to all '0's.
Afterward, convert a contiguous block of '0's that is surrounded by '1's to all '1's.

Return the maximum number of active sections in s after making the optimal trade.
Note: Treat s as if it is augmented with a '1' at both ends, forming t = '1' + s + '1'. The augmented '1's do not contribute to the final count.

Example 1:

Input: s = "01"
Output: 1
Explanation:
Because there is no block of '1's surrounded by '0's, no valid trade is possible. The maximum number of active sections is 1.

Example 2:

Input: s = "0100"
Output: 4
Explanation:

String "0100" → Augmented to "101001".
Choose "0100", convert "101001" → "100001" → "111111".
The final string without augmentation is "1111". The maximum number of active sections is 4.

Example 3:

Input: s = "1000100"
Output: 7
Explanation:

String "1000100" → Augmented to "110001001".
Choose "000100", convert "110001001" → "110000001" → "111111111".
The final string without augmentation is "1111111". The maximum number of active sections is 7.

Example 4:

Input: s = "01010"
Output: 4
Explanation:

String "01010" → Augmented to "1010101".
Choose "010", convert "1010101" → "1000101" → "1111101".
The final string without augmentation is "11110". The maximum number of active sections is 4.

Constraints:

1 <= n == s.length <= 105
s[i] is either '0' or '1'

Your solution to the problem should be a method of the class Solution called maxActiveSectionsAfterTrade and should pass all tests. Use the following starter code:
```python
class Solution:
    def maxActiveSectionsAfterTrade(self, s: str) -> int:
        # Add your code here
```

SOLUTION:

Question:
PROBLEM:
You are given a binary string s of length n, where:

'1' represents an active section.
'0' represents an inactive section.

You can perform at most one trade to maximize the number of active sections in s. In a trade, you:

Convert a contiguous block of '1's that is surrounded by '0's to all '0's.
Afterward, convert a contiguous block of '0's that is surrounded by '1's to all '1's.

Return the maximum number of active sections in s after making the optimal trade.
Note: Treat s as if it is augmented with a '1' at both ends, forming t = '1' + s + '1'. The augmented '1's do not contribute to the final count.

Example 1:

Input: s = "01"
Output: 1
Explanation:
Because there is no block of '1's surrounded by '0's, no valid trade is possible. The maximum number of active sections is 1.

Example 2:

Input: s = "0100"
Output: 4
Explanation:

String "0100" → Augmented to "101001".
Choose "0100", convert "101001" → "100001" → "111111".
The final string without augmentation is "1111". The maximum number of active sections is 4.

Example 3:

Input: s = "1000100"
Output: 7
Explanation:

String "1000100" → Augmented to "110001001".
Choose "000100", convert "110001001" → "110000001" → "111111111".
The final string without augmentation is "1111111". The maximum number of active sections is 7.

Example 4:

Input: s = "01010"
Output: 4
Explanation:

String "01010" → Augmented to "1010101".
Choose "010", convert "1010101" → "1000101" → "1111101".
The final string without augmentation is "11110". The maximum number of active sections is 4.

Constraints:

1 <= n == s.length <= 105
s[i] is either '0' or '1'

Your solution to the problem should be a method of the class Solution called maxActiveSectionsAfterTrade and should pass all tests. Use the following starter code:
```python
class Solution:
    def maxActiveSectionsAfterTrade(self, s: str) -> int:
        # Add your code here
```

SOLUTION:

assert Solution().maxActiveSectionsAfterTrade(s = "01010") == 4

assert Solution().maxActiveSectionsAfterTrade(s = "1000100") == 7

assert Solution().maxActiveSectionsAfterTrade(s = "010101010") == 6

assert Solution().maxActiveSectionsAfterTrade(s = "1001001001") == 8

assert Solution().maxActiveSectionsAfterTrade(s = "11111") == 5

assert Solution().maxActiveSectionsAfterTrade(s = "0011001100") == 8

assert Solution().maxActiveSectionsAfterTrade(s = "1100110011") == 10

assert Solution().maxActiveSectionsAfterTrade(s = "000") == 0

assert Solution().maxActiveSectionsAfterTrade(s = "0101010101") == 7

assert Solution().maxActiveSectionsAfterTrade(s = "01") == 1

assert Solution().maxActiveSectionsAfterTrade(s = "101010101") == 7

assert Solution().maxActiveSectionsAfterTrade(s = "10101010101") == 8

assert Solution().maxActiveSectionsAfterTrade(s = "0100") == 4

assert Solution().maxActiveSectionsAfterTrade(s = "00000") == 0

assert Solution().maxActiveSectionsAfterTrade(s = "01001001001") == 8

assert Solution().maxActiveSectionsAfterTrade(s = "111") == 3

assert Solution().maxActiveSectionsAfterTrade(s = "000000000000000000000") == 0

assert Solution().maxActiveSectionsAfterTrade(s = "11100111001110011100111") == 19

assert Solution().maxActiveSectionsAfterTrade(s = "1000001000001000001000001") == 15

assert Solution().maxActiveSectionsAfterTrade(s = "010101010101010101010") == 12

assert Solution().maxActiveSectionsAfterTrade(s = "010100101001010010100101001") == 14

assert Solution().maxActiveSectionsAfterTrade(s = "1111000011110000111100001111") == 24

assert Solution().maxActiveSectionsAfterTrade(s = "110000010001001000010000001") == 17

assert Solution().maxActiveSectionsAfterTrade(s = "101010101010101010101") == 13

assert Solution().maxActiveSectionsAfterTrade(s = "111111111111111111111") == 21

assert Solution().maxActiveSectionsAfterTrade(s = "00100000100000100000100000100") == 15

assert Solution().maxActiveSectionsAfterTrade(s = "111000111000111000111") == 18

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01010") == 4

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1000100") == 7

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "010101010") == 6

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1001001001") == 8

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11111") == 5

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0011001100") == 8

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1100110011") == 10

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "000") == 0

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0101010101") == 7

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01") == 1

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "101010101") == 7

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "10101010101") == 8

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0100") == 4

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00000") == 0

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01001001001") == 8

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111") == 3

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "001100110011001100110011001100110011001100110011") == 28

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "000000000000000000000") == 0

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "000000111111000000111111000000111111000000111111") == 36

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "100000100000100000100000100000100000100000100000") == 18

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0011001100110011001100110011001100110011001100110011001100110011") == 36

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11001100110011001100110011001100110011001100110011001100110011001100") == 38

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1111100000111110000011111000001111100000111110000011111000001111100000") == 45

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00011001100110011001100110011001100110011001100110011001100110011001100") == 39

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0100100100100100100100100100100100100100100100100100100100100100100100100") == 28

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "100100100100100100100100100100100100100100100100100100100100100100100100") == 28

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01010101010101010101010101010101010101010101010101010101") == 30

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11100111001110011100111") == 19

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "10101010101010101010101010101010101010101010") == 24

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "10101010101010101010101010101010101010101010101010101010101") == 32

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "001001001001001001001001001001001001001001001001001001001001001") == 25

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111111111111111111111111111111111111111111111111") == 48

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11111111111111111111111111111111111111111111111111111111") == 56

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111000100110011001100110011001100110011001100110") == 29

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "101010101010101010101010101010101010101010101010") == 26

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "000111000111000111000111000111000111000111000111000111000") == 33

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1111111111111111111111111111111111111111111111111111111111110") == 60

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1000001000001000001000001") == 15

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111000111000111000111000111000111000111000111000111000111000111") == 39

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "010101010101010101010") == 12

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1000100010001000100010001000100010001000100010001") == 19

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "010100101001010010100101001") == 14

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0101010101010101010101010101010101010101010101010101010101") == 31

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "010101010101010101010101010101010101010101010101") == 26

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "000000000000000000000000000000000000000000000001") == 1

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111000111000111000111000111000111000111000111000111000111000111000") == 39

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "010101010101010101010101010101010101010101010101010101010101010101010101") == 38

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11010001110110000100110110001001110110011011000110110") == 33

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01110111011101110111011101110111011101110111011101110111") == 44

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1111000011110000111100001111") == 24

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "000111000111000111000111000111000111") == 24

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1000001000001000001000001000001000001000001000001") == 19

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11110000111100001111000011110000111100001111000011110000111100001111") == 44

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0000011111000001111100000111110000011111000001111100000111110000011111") == 45

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "001001001001001001001001001001001001001001001001001001") == 22

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01001001001001001001001001001001001001001001001001001001001001") == 25

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111111111111111111111111111111111111111111111110") == 47

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "10000010001000001000001000001000001000001000001000001000001") == 21

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00111000111000111000111000111000111000111000111000111000111000111000") == 39

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "110001100011000110001100011000110001100011000110001100011000110001100011") == 36

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1000000000000000000000000000000000000000000000000000000000001") == 2

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0101010101010101010101010101010101010101010101010101010101010101") == 34

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01010101010101010101010101010101010101010101") == 24

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "011001100110011001100110011001100110011001100110") == 28

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "110000010001001000010000001") == 17

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1001001001001001001001001001001001001001001001001001001001001001001") == 27

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11111110000011111100000000011111111111111100000011111111") == 51

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01000100010001000100010001000100010001") == 16

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11111111111111111111111111111111111111111111111111111111111111111111111") == 71

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111000111000111000111000111000111000111000111000111000111") == 36

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "110011001100110011001100110011001100110011001100") == 28

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00001111000011110000111100001111000011110000111100001111000011110000") == 40

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "101010101010101010101") == 13

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111111000000111111000000111111000000111111") == 36

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111111111111111111111") == 21

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "01100110011001100110011001100110011001100110011001100110011001100") == 36

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00100000100000100000100000100") == 15

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0011001100110011001100110011001100110011001100110011001100110011001100") == 38

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00100100100100100100100100100100100100100100100100100100100100100") == 25

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "1010101010101010101010101010101010101010101010101010101010101010") == 34

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00000000000000000000000000000000000000000000000000000000") == 0

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111111111111111111111111111111111111111111111111111111") == 54

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "00001111000011110000111100001111") == 24

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "101010101010101010101010101010101010101010101010101010101010101010101010") == 38

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "11001100110011001100110011001100110011") == 24

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "000000000000000000000000000000000000000000000000") == 0

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "0000000000000000000000000000000000000000000000000000000000000000000000") == 0

Answer: assert Solution().maxActiveSectionsAfterTrade(s = "111000111000111000111") == 18

import random
import functools
import collections
import string
import math
import datetime

from typing import *
from functools import *
from collections import *
from itertools import *
from heapq import *
from bisect import *
from string import *
from operator import *
from math import *

inf = float('inf')

class ListNode:
    def __init__(self, val=0, next=None):
        self.val = val
        self.next = next

def list_node(values: list):
    if not values:
        return None
    head = ListNode(values[0])
    p = head
    for val in values[1:]:
        node = ListNode(val)
        p.next = node
        p = node
    return head

def is_same_list(p1, p2):
    if p1 is None and p2 is None:
        return True
    if not p1 or not p2:
        return False
    return p1.val == p2.val and is_same_list(p1.next, p2.next)

class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right

def tree_node(values: list):
    if not values:
        return None
    root = TreeNode(values[0])
    i = 1
    queue = deque()
    queue.append(root)
    while queue:
        node = queue.popleft()
        if i < len(values) and values[i] is not None:
            node.left = TreeNode(values[i])
            queue.append(node.left)
        i += 1
        if i < len(values) and values[i] is not None:
            node.right = TreeNode(values[i])
            queue.append(node.right)
        i += 1
    return root

def is_same_tree(p, q):
    if not p and not q:
        return True
    elif not p or not q:
        return False
    elif p.val != q.val:
        return False
    else:
        return is_same_tree(p.left, q.left) and is_same_tree(p.right, q.right)

class Solution:
    def maxActiveSectionsAfterTrade(self, s: str) -> int:
        n = len(s)
        ans = i = 0
        pre, mx = -inf, 0
        while i < n:
            j = i + 1
            while j < n and s[j] == s[i]:
                j += 1
            cur = j - i
            if s[i] == "1":
                ans += cur
            else:
                mx = max(mx, pre + cur)
                pre = cur
            i = j
        ans += mx
        return ans


You are an expert Python programmer. Write correct, efficient Python 3 code that solves the problem and passes all tests. Output the code in the following format: ```python
<code>
```

PROBLEM:
You are given two strings, s and t.
You can create a new string by selecting a substring from s (possibly empty) and a substring from t (possibly empty), then concatenating them in order.
Return the length of the longest palindrome that can be formed this way.

Example 1:

Input: s = "a", t = "a"
Output: 2
Explanation:
Concatenating "a" from s and "a" from t results in "aa", which is a palindrome of length 2.

Example 2:

Input: s = "abc", t = "def"
Output: 1
Explanation:
Since all characters are different, the longest palindrome is any single character, so the answer is 1.

Example 3:

Input: s = "b", t = "aaaa"
Output: 4
Explanation:
Selecting "aaaa" from t is the longest palindrome, so the answer is 4.

Example 4:

Input: s = "abcde", t = "ecdba"
Output: 5
Explanation:
Concatenating "abc" from s and "ba" from t results in "abcba", which is a palindrome of length 5.

Constraints:

1 <= s.length, t.length <= 30
s and t consist of lowercase English letters.

Your solution to the problem should be a method of the class Solution called longestPalindrome and should pass all tests. Use the following starter code:
```python
class Solution:
    def longestPalindrome(self, s: str, t: str) -> int:
        # Add your code here
```

SOLUTION:

Question:
PROBLEM:
You are given two strings, s and t.
You can create a new string by selecting a substring from s (possibly empty) and a substring from t (possibly empty), then concatenating them in order.
Return the length of the longest palindrome that can be formed this way.

Example 1:

Input: s = "a", t = "a"
Output: 2
Explanation:
Concatenating "a" from s and "a" from t results in "aa", which is a palindrome of length 2.

Example 2:

Input: s = "abc", t = "def"
Output: 1
Explanation:
Since all characters are different, the longest palindrome is any single character, so the answer is 1.

Example 3:

Input: s = "b", t = "aaaa"
Output: 4
Explanation:
Selecting "aaaa" from t is the longest palindrome, so the answer is 4.

Example 4:

Input: s = "abcde", t = "ecdba"
Output: 5
Explanation:
Concatenating "abc" from s and "ba" from t results in "abcba", which is a palindrome of length 5.

Constraints:

1 <= s.length, t.length <= 30
s and t consist of lowercase English letters.

Your solution to the problem should be a method of the class Solution called longestPalindrome and should pass all tests. Use the following starter code:
```python
class Solution:
    def longestPalindrome(self, s: str, t: str) -> int:
        # Add your code here
```

SOLUTION:

assert Solution().longestPalindrome(s = "b", t = "aaaa") == 4

assert Solution().longestPalindrome(s = "hello", t = "world") == 3

assert Solution().longestPalindrome(s = "different", t = "entirely") == 5

assert Solution().longestPalindrome(s = "level", t = "deified") == 7

assert Solution().longestPalindrome(s = "xyza", t = "azxy") == 4

assert Solution().longestPalindrome(s = "abcabc", t = "cbacba") == 12

assert Solution().longestPalindrome(s = "race", t = "ecar") == 8

assert Solution().longestPalindrome(s = "abcde", t = "ecdba") == 5

assert Solution().longestPalindrome(s = "noon", t = "moon") == 7

assert Solution().longestPalindrome(s = "race", t = "care") == 7

assert Solution().longestPalindrome(s = "a", t = "a") == 2

assert Solution().longestPalindrome(s = "hello", t = "olleh") == 10

assert Solution().longestPalindrome(s = "abcd", t = "dcba") == 8

assert Solution().longestPalindrome(s = "xyz", t = "zyx") == 6

assert Solution().longestPalindrome(s = "same", t = "same") == 3

assert Solution().longestPalindrome(s = "abc", t = "def") == 1

assert Solution().longestPalindrome(s = "abac", t = "cab") == 6

assert Solution().longestPalindrome(s = "ab", t = "ba") == 4

assert Solution().longestPalindrome(s = "mississippi", t = "pip") == 7

assert Solution().longestPalindrome(s = "aabbcc", t = "ccbbaa") == 12

assert Solution().longestPalindrome(s = "rotor", t = "rotorrotor") == 15

assert Solution().longestPalindrome(s = "xyxyxyxy", t = "yxyxyxyx") == 16

assert Solution().longestPalindrome(s = "noonracecar", t = "racecarnoon") == 22

assert Solution().longestPalindrome(s = "aaaaabbbbbaaaa", t = "bbbbbaaaaabbbb") == 24

assert Solution().longestPalindrome(s = "abcdefg", t = "gfedcba") == 14

assert Solution().longestPalindrome(s = "step", t = "pots") == 5

assert Solution().longestPalindrome(s = "madam", t = "madame") == 10

assert Solution().longestPalindrome(s = "abababab", t = "babababa") == 16

assert Solution().longestPalindrome(s = "madam", t = "madam") == 10

assert Solution().longestPalindrome(s = "xyzxyzxyz", t = "zyxzyxzyx") == 18

assert Solution().longestPalindrome(s = "palindrome", t = "emordnilap") == 20

assert Solution().longestPalindrome(s = "zyxwvutsrqponmlkjihgfedcba", t = "abcdefghijklmnopqrstuvwxyz") == 52

assert Solution().longestPalindrome(s = "pneumonoultramicroscopicsilicovolcanoconiosis", t = "coniosisvolcanosilicovolcanoultramicroscopicneumo") == 7

assert Solution().longestPalindrome(s = "noonrace", t = "carenood") == 7

assert Solution().longestPalindrome(s = "abccba", t = "abcabc") == 7

assert Solution().longestPalindrome(s = "anana", t = "ananana") == 11

assert Solution().longestPalindrome(s = "xyzzzzxy", t = "zzzz") == 9

assert Solution().longestPalindrome(s = "madam", t = "madamracecar") == 10

assert Solution().longestPalindrome(s = "detartrated", t = "deified") == 11

assert Solution().longestPalindrome(s = "abccba", t = "xyzzyx") == 6

assert Solution().longestPalindrome(s = "civic", t = "reviver") == 7

assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdfgdcaba") == 11

assert Solution().longestPalindrome(s = "abacabadaba", t = "babadacaba") == 15

assert Solution().longestPalindrome(s = "abba", t = "bbaa") == 7

assert Solution().longestPalindrome(s = "refer", t = "refer") == 10

assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbaab") == 18

assert Solution().longestPalindrome(s = "xyzzyx", t = "zyxyzyx") == 9

assert Solution().longestPalindrome(s = "abcdabcd", t = "dcbaabcd") == 9

assert Solution().longestPalindrome(s = "abcba", t = "abcba") == 10

assert Solution().longestPalindrome(s = "xyx", t = "yxyyxyx") == 8

assert Solution().longestPalindrome(s = "deified", t = "deifiedlevel") == 14

assert Solution().longestPalindrome(s = "refer", t = "referrefer") == 15

assert Solution().longestPalindrome(s = "deified", t = "madam") == 7

assert Solution().longestPalindrome(s = "longerstring", t = "stringlonger") == 3

assert Solution().longestPalindrome(s = "testset", t = "tset") == 9

assert Solution().longestPalindrome(s = "abacaxaba", t = "abcdeab") == 5

assert Solution().longestPalindrome(s = "xyzabcabc", t = "cbabczyx") == 11

assert Solution().longestPalindrome(s = "abcdxyz", t = "zyxcba") == 7

assert Solution().longestPalindrome(s = "noonhighnoon", t = "noonlownoon") == 9

assert Solution().longestPalindrome(s = "zzzzz", t = "yyyyy") == 5

assert Solution().longestPalindrome(s = "abcdefghijk", t = "zyxwvutsrqp") == 1

assert Solution().longestPalindrome(s = "civic", t = "refer") == 5

assert Solution().longestPalindrome(s = "madamimadam", t = "madaminimadam") == 17

assert Solution().longestPalindrome(s = "kayak", t = "tenet") == 5

assert Solution().longestPalindrome(s = "aaabaaa", t = "aaaaaaa") == 10

assert Solution().longestPalindrome(s = "abccba", t = "baccab") == 6

assert Solution().longestPalindrome(s = "pqrstu", t = "utrspq") == 4

assert Solution().longestPalindrome(s = "abcdefghi", t = "ihgfedcba") == 18

assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "bagxacdgadb") == 9

assert Solution().longestPalindrome(s = "noonnoon", t = "noonnoon") == 16

assert Solution().longestPalindrome(s = "abacaba", t = "badacab") == 9

assert Solution().longestPalindrome(s = "mississippi", t = "pississim") == 19

assert Solution().longestPalindrome(s = "noonhighnoon", t = "noon") == 9

assert Solution().longestPalindrome(s = "mnopqrstuv", t = "vutsrqponm") == 20

assert Solution().longestPalindrome(s = "aabbccddeeffgghhiijjkkll", t = "llkkjjiihhggffeeeeddccbaab") == 32

assert Solution().longestPalindrome(s = "mnopqr", t = "rqponm") == 12

assert Solution().longestPalindrome(s = "aaaaaaab", t = "bbbaaaaa") == 14

assert Solution().longestPalindrome(s = "radar", t = "level") == 5

assert Solution().longestPalindrome(s = "mississippi", t = "ppississimm") == 21

assert Solution().longestPalindrome(s = "pqrstu", t = "utsrpq") == 8

assert Solution().longestPalindrome(s = "racecar", t = "carrace") == 9

assert Solution().longestPalindrome(s = "abacabadabacaba", t = "badacabadacab") == 15

assert Solution().longestPalindrome(s = "aaabaaa", t = "bbbabb") == 7

assert Solution().longestPalindrome(s = "banana", t = "ananab") == 12

assert Solution().longestPalindrome(s = "noon", t = "moonnoon") == 9

assert Solution().longestPalindrome(s = "wow", t = "wowow") == 7

assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbbaa") == 24

assert Solution().longestPalindrome(s = "abracadabra", t = "arbadacarba") == 22

assert Solution().longestPalindrome(s = "mom", t = "momom") == 7

assert Solution().longestPalindrome(s = "abcdefghijklmnopqrstuvwxyz", t = "zyxwvutsrqponmlkjihgfedcba") == 52

assert Solution().longestPalindrome(s = "ananab", t = "banana") == 12

assert Solution().longestPalindrome(s = "abcxyz", t = "zyxcba") == 12

assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdgfdcaba") == 24

assert Solution().longestPalindrome(s = "racecar", t = "civicracecar") == 19

assert Solution().longestPalindrome(s = "madam", t = "detartrated") == 11

assert Solution().longestPalindrome(s = "aaaaaaa", t = "bbbbbbb") == 7

assert Solution().longestPalindrome(s = "aabaaaabbbaa", t = "bbbaaaaabbaa") == 16

assert Solution().longestPalindrome(s = "racecar", t = "racecar") == 14

assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbaa") == 18

assert Solution().longestPalindrome(s = "pqrstuvwxyz", t = "zyxwvutsrqponmlkjihgfedcba") == 22

assert Solution().longestPalindrome(s = "rotor", t = "rotor") == 10

Answer: assert Solution().longestPalindrome(s = "b", t = "aaaa") == 4

Answer: assert Solution().longestPalindrome(s = "hello", t = "world") == 3

Answer: assert Solution().longestPalindrome(s = "different", t = "entirely") == 5

Answer: assert Solution().longestPalindrome(s = "level", t = "deified") == 7

Answer: assert Solution().longestPalindrome(s = "xyza", t = "azxy") == 4

Answer: assert Solution().longestPalindrome(s = "abcabc", t = "cbacba") == 12

Answer: assert Solution().longestPalindrome(s = "race", t = "ecar") == 8

Answer: assert Solution().longestPalindrome(s = "abcde", t = "ecdba") == 5

Answer: assert Solution().longestPalindrome(s = "noon", t = "moon") == 7

Answer: assert Solution().longestPalindrome(s = "race", t = "care") == 7

Answer: assert Solution().longestPalindrome(s = "a", t = "a") == 2

Answer: assert Solution().longestPalindrome(s = "hello", t = "olleh") == 10

Answer: assert Solution().longestPalindrome(s = "abcd", t = "dcba") == 8

Answer: assert Solution().longestPalindrome(s = "xyz", t = "zyx") == 6

Answer: assert Solution().longestPalindrome(s = "same", t = "same") == 3

Answer: assert Solution().longestPalindrome(s = "abc", t = "def") == 1

Answer: assert Solution().longestPalindrome(s = "abac", t = "cab") == 6

Answer: assert Solution().longestPalindrome(s = "ab", t = "ba") == 4

Answer: assert Solution().longestPalindrome(s = "mississippi", t = "pip") == 7

Answer: assert Solution().longestPalindrome(s = "aabbcc", t = "ccbbaa") == 12

Answer: assert Solution().longestPalindrome(s = "rotor", t = "rotorrotor") == 15

Answer: assert Solution().longestPalindrome(s = "xyxyxyxy", t = "yxyxyxyx") == 16

Answer: assert Solution().longestPalindrome(s = "noonracecar", t = "racecarnoon") == 22

Answer: assert Solution().longestPalindrome(s = "aaaaabbbbbaaaa", t = "bbbbbaaaaabbbb") == 24

Answer: assert Solution().longestPalindrome(s = "abcdefg", t = "gfedcba") == 14

Answer: assert Solution().longestPalindrome(s = "step", t = "pots") == 5

Answer: assert Solution().longestPalindrome(s = "madam", t = "madame") == 10

Answer: assert Solution().longestPalindrome(s = "abababab", t = "babababa") == 16

Answer: assert Solution().longestPalindrome(s = "madam", t = "madam") == 10

Answer: assert Solution().longestPalindrome(s = "xyzxyzxyz", t = "zyxzyxzyx") == 18

Answer: assert Solution().longestPalindrome(s = "palindrome", t = "emordnilap") == 20

Answer: assert Solution().longestPalindrome(s = "zyxwvutsrqponmlkjihgfedcba", t = "abcdefghijklmnopqrstuvwxyz") == 52

Answer: assert Solution().longestPalindrome(s = "pneumonoultramicroscopicsilicovolcanoconiosis", t = "coniosisvolcanosilicovolcanoultramicroscopicneumo") == 7

Answer: assert Solution().longestPalindrome(s = "noonrace", t = "carenood") == 7

Answer: assert Solution().longestPalindrome(s = "abccba", t = "abcabc") == 7

Answer: assert Solution().longestPalindrome(s = "anana", t = "ananana") == 11

Answer: assert Solution().longestPalindrome(s = "xyzzzzxy", t = "zzzz") == 9

Answer: assert Solution().longestPalindrome(s = "madam", t = "madamracecar") == 10

Answer: assert Solution().longestPalindrome(s = "detartrated", t = "deified") == 11

Answer: assert Solution().longestPalindrome(s = "abccba", t = "xyzzyx") == 6

Answer: assert Solution().longestPalindrome(s = "civic", t = "reviver") == 7

Answer: assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdfgdcaba") == 11

Answer: assert Solution().longestPalindrome(s = "abacabadaba", t = "babadacaba") == 15

Answer: assert Solution().longestPalindrome(s = "abba", t = "bbaa") == 7

Answer: assert Solution().longestPalindrome(s = "refer", t = "refer") == 10

Answer: assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbaab") == 18

Answer: assert Solution().longestPalindrome(s = "xyzzyx", t = "zyxyzyx") == 9

Answer: assert Solution().longestPalindrome(s = "abcdabcd", t = "dcbaabcd") == 9

Answer: assert Solution().longestPalindrome(s = "abcba", t = "abcba") == 10

Answer: assert Solution().longestPalindrome(s = "xyx", t = "yxyyxyx") == 8

Answer: assert Solution().longestPalindrome(s = "deified", t = "deifiedlevel") == 14

Answer: assert Solution().longestPalindrome(s = "refer", t = "referrefer") == 15

Answer: assert Solution().longestPalindrome(s = "deified", t = "madam") == 7

Answer: assert Solution().longestPalindrome(s = "longerstring", t = "stringlonger") == 3

Answer: assert Solution().longestPalindrome(s = "testset", t = "tset") == 9

Answer: assert Solution().longestPalindrome(s = "abacaxaba", t = "abcdeab") == 5

Answer: assert Solution().longestPalindrome(s = "xyzabcabc", t = "cbabczyx") == 11

Answer: assert Solution().longestPalindrome(s = "abcdxyz", t = "zyxcba") == 7

Answer: assert Solution().longestPalindrome(s = "noonhighnoon", t = "noonlownoon") == 9

Answer: assert Solution().longestPalindrome(s = "zzzzz", t = "yyyyy") == 5

Answer: assert Solution().longestPalindrome(s = "abcdefghijk", t = "zyxwvutsrqp") == 1

Answer: assert Solution().longestPalindrome(s = "civic", t = "refer") == 5

Answer: assert Solution().longestPalindrome(s = "madamimadam", t = "madaminimadam") == 17

Answer: assert Solution().longestPalindrome(s = "kayak", t = "tenet") == 5

Answer: assert Solution().longestPalindrome(s = "aaabaaa", t = "aaaaaaa") == 10

Answer: assert Solution().longestPalindrome(s = "abccba", t = "baccab") == 6

Answer: assert Solution().longestPalindrome(s = "pqrstu", t = "utrspq") == 4

Answer: assert Solution().longestPalindrome(s = "abcdefghi", t = "ihgfedcba") == 18

Answer: assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "bagxacdgadb") == 9

Answer: assert Solution().longestPalindrome(s = "noonnoon", t = "noonnoon") == 16

Answer: assert Solution().longestPalindrome(s = "abacaba", t = "badacab") == 9

Answer: assert Solution().longestPalindrome(s = "mississippi", t = "pississim") == 19

Answer: assert Solution().longestPalindrome(s = "noonhighnoon", t = "noon") == 9

Answer: assert Solution().longestPalindrome(s = "mnopqrstuv", t = "vutsrqponm") == 20

Answer: assert Solution().longestPalindrome(s = "aabbccddeeffgghhiijjkkll", t = "llkkjjiihhggffeeeeddccbaab") == 32

Answer: assert Solution().longestPalindrome(s = "mnopqr", t = "rqponm") == 12

Answer: assert Solution().longestPalindrome(s = "aaaaaaab", t = "bbbaaaaa") == 14

Answer: assert Solution().longestPalindrome(s = "radar", t = "level") == 5

Answer: assert Solution().longestPalindrome(s = "mississippi", t = "ppississimm") == 21

Answer: assert Solution().longestPalindrome(s = "pqrstu", t = "utsrpq") == 8

Answer: assert Solution().longestPalindrome(s = "racecar", t = "carrace") == 9

Answer: assert Solution().longestPalindrome(s = "abacabadabacaba", t = "badacabadacab") == 15

Answer: assert Solution().longestPalindrome(s = "aaabaaa", t = "bbbabb") == 7

Answer: assert Solution().longestPalindrome(s = "banana", t = "ananab") == 12

Answer: assert Solution().longestPalindrome(s = "noon", t = "moonnoon") == 9

Answer: assert Solution().longestPalindrome(s = "wow", t = "wowow") == 7

Answer: assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbbaa") == 24

Answer: assert Solution().longestPalindrome(s = "abracadabra", t = "arbadacarba") == 22

Answer: assert Solution().longestPalindrome(s = "mom", t = "momom") == 7

Answer: assert Solution().longestPalindrome(s = "abcdefghijklmnopqrstuvwxyz", t = "zyxwvutsrqponmlkjihgfedcba") == 52

Answer: assert Solution().longestPalindrome(s = "ananab", t = "banana") == 12

Answer: assert Solution().longestPalindrome(s = "abcxyz", t = "zyxcba") == 12

Answer: assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdgfdcaba") == 24

Answer: assert Solution().longestPalindrome(s = "racecar", t = "civicracecar") == 19

Answer: assert Solution().longestPalindrome(s = "madam", t = "detartrated") == 11

Answer: assert Solution().longestPalindrome(s = "aaaaaaa", t = "bbbbbbb") == 7

Answer: assert Solution().longestPalindrome(s = "aabaaaabbbaa", t = "bbbaaaaabbaa") == 16

Answer: assert Solution().longestPalindrome(s = "racecar", t = "racecar") == 14

Answer: assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbaa") == 18

Answer: assert Solution().longestPalindrome(s = "pqrstuvwxyz", t = "zyxwvutsrqponmlkjihgfedcba") == 22

Answer: assert Solution().longestPalindrome(s = "rotor", t = "rotor") == 10

import random
import functools
import collections
import string
import math
import datetime

from typing import *
from functools import *
from collections import *
from itertools import *
from heapq import *
from bisect import *
from string import *
from operator import *
from math import *

inf = float('inf')

class ListNode:
    def __init__(self, val=0, next=None):
        self.val = val
        self.next = next

def list_node(values: list):
    if not values:
        return None
    head = ListNode(values[0])
    p = head
    for val in values[1:]:
        node = ListNode(val)
        p.next = node
        p = node
    return head

def is_same_list(p1, p2):
    if p1 is None and p2 is None:
        return True
    if not p1 or not p2:
        return False
    return p1.val == p2.val and is_same_list(p1.next, p2.next)

class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right

def tree_node(values: list):
    if not values:
        return None
    root = TreeNode(values[0])
    i = 1
    queue = deque()
    queue.append(root)
    while queue:
        node = queue.popleft()
        if i < len(values) and values[i] is not None:
            node.left = TreeNode(values[i])
            queue.append(node.left)
        i += 1
        if i < len(values) and values[i] is not None:
            node.right = TreeNode(values[i])
            queue.append(node.right)
        i += 1
    return root

def is_same_tree(p, q):
    if not p and not q:
        return True
    elif not p or not q:
        return False
    elif p.val != q.val:
        return False
    else:
        return is_same_tree(p.left, q.left) and is_same_tree(p.right, q.right)

class Solution:
    def calc(self, s: str, t: str) -> int:
        n, m = len(s), len(t)
        f = [[0] * (m + 1) for _ in range(n + 1)]
        for i, x in enumerate(s):
            for j, y in enumerate(t):
                if x == y:
                    f[i + 1][j] = f[i][j + 1] + 1
        mx = list(map(max, f))
        ans = max(mx) * 2  # |x| = |y| 的情况

        # 计算 |x| > |y| 的情况，中心扩展法
        for i in range(2 * n - 1):
            l, r = i // 2, (i + 1) // 2
            while l >= 0 and r < n and s[l] == s[r]:
                l -= 1
                r += 1
            if l + 1 <= r - 1:  # s[l+1] 到 s[r-1] 是非空回文串
                ans = max(ans, r - l - 1 + mx[l + 1] * 2)
        return ans

    def longestPalindrome(self, s: str, t: str) -> int:
        return max(self.calc(s, t), self.calc(t[::-1], s[::-1]))

class Solution:
    def longestPalindrome(self, s: str, t: str) -> int:


You are an expert Python programmer. Write correct, efficient Python 3 code that solves the problem and passes all tests. Output the code in the following format: ```python
<code>
```

PROBLEM:
You are given two strings, s and t.
You can create a new string by selecting a substring from s (possibly empty) and a substring from t (possibly empty), then concatenating them in order.
Return the length of the longest palindrome that can be formed this way.

Example 1:

Input: s = "a", t = "a"
Output: 2
Explanation:
Concatenating "a" from s and "a" from t results in "aa", which is a palindrome of length 2.

Example 2:

Input: s = "abc", t = "def"
Output: 1
Explanation:
Since all characters are different, the longest palindrome is any single character, so the answer is 1.

Example 3:

Input: s = "b", t = "aaaa"
Output: 4
Explanation:
Selecting "aaaa" from t is the longest palindrome, so the answer is 4.

Example 4:

Input: s = "abcde", t = "ecdba"
Output: 5
Explanation:
Concatenating "abc" from s and "ba" from t results in "abcba", which is a palindrome of length 5.

Constraints:

1 <= s.length, t.length <= 1000
s and t consist of lowercase English letters.

Your solution to the problem should be a method of the class Solution called longestPalindrome and should pass all tests. Use the following starter code:
```python
class Solution:
    def longestPalindrome(self, s: str, t: str) -> int:
        # Add your code here
```

SOLUTION:

Question:
PROBLEM:
You are given two strings, s and t.
You can create a new string by selecting a substring from s (possibly empty) and a substring from t (possibly empty), then concatenating them in order.
Return the length of the longest palindrome that can be formed this way.

Example 1:

Input: s = "a", t = "a"
Output: 2
Explanation:
Concatenating "a" from s and "a" from t results in "aa", which is a palindrome of length 2.

Example 2:

Input: s = "abc", t = "def"
Output: 1
Explanation:
Since all characters are different, the longest palindrome is any single character, so the answer is 1.

Example 3:

Input: s = "b", t = "aaaa"
Output: 4
Explanation:
Selecting "aaaa" from t is the longest palindrome, so the answer is 4.

Example 4:

Input: s = "abcde", t = "ecdba"
Output: 5
Explanation:
Concatenating "abc" from s and "ba" from t results in "abcba", which is a palindrome of length 5.

Constraints:

1 <= s.length, t.length <= 1000
s and t consist of lowercase English letters.

Your solution to the problem should be a method of the class Solution called longestPalindrome and should pass all tests. Use the following starter code:
```python
class Solution:
    def longestPalindrome(self, s: str, t: str) -> int:
        # Add your code here
```

SOLUTION:

assert Solution().longestPalindrome(s = "b", t = "aaaa") == 4

assert Solution().longestPalindrome(s = "hello", t = "world") == 3

assert Solution().longestPalindrome(s = "aaaa", t = "bbbb") == 4

assert Solution().longestPalindrome(s = "abcde", t = "ecdba") == 5

assert Solution().longestPalindrome(s = "noon", t = "moon") == 7

assert Solution().longestPalindrome(s = "race", t = "care") == 7

assert Solution().longestPalindrome(s = "a", t = "a") == 2

assert Solution().longestPalindrome(s = "abcd", t = "dcba") == 8

assert Solution().longestPalindrome(s = "xyz", t = "zyx") == 6

assert Solution().longestPalindrome(s = "abc", t = "def") == 1

assert Solution().longestPalindrome(s = "referrefer", t = "referref") == 16

assert Solution().longestPalindrome(s = "abccba", t = "abcba") == 7

assert Solution().longestPalindrome(s = "abcabc", t = "cbacba") == 12

assert Solution().longestPalindrome(s = "mnopqr", t = "rqpomn") == 8

assert Solution().longestPalindrome(s = "rotorrotor", t = "rotorrot") == 16

assert Solution().longestPalindrome(s = "madam", t = "madammadam") == 15

assert Solution().longestPalindrome(s = "aabbaabb", t = "bbaa") == 10

assert Solution().longestPalindrome(s = "aaaaabbbbb", t = "bbbbbbaaaa") == 19

assert Solution().longestPalindrome(s = "abccba", t = "bccbab") == 11

assert Solution().longestPalindrome(s = "aabbcc", t = "ccbbaa") == 12

assert Solution().longestPalindrome(s = "abcdef", t = "fedabc") == 6

assert Solution().longestPalindrome(s = "xyxyxy", t = "yxyxyx") == 12

assert Solution().longestPalindrome(s = "aba", t = "bab") == 5

assert Solution().longestPalindrome(s = "abcdefg", t = "gfedcba") == 14

assert Solution().longestPalindrome(s = "tatactatta", t = "tatattac") == 11

assert Solution().longestPalindrome(s = "madam", t = "madam") == 10

assert Solution().longestPalindrome(s = "aabaa", t = "bbabb") == 6

assert Solution().longestPalindrome(s = "abcdef", t = "fedcbaghi") == 12

assert Solution().longestPalindrome(s = "palindrome", t = "emordnilap") == 20

assert Solution().longestPalindrome(s = "xyzaaayzx", t = "zyxxzyxzy") == 9

assert Solution().longestPalindrome(s = "abcabcabc", t = "cbacbacba") == 18

assert Solution().longestPalindrome(s = "pqr", t = "rqp") == 6

assert Solution().longestPalindrome(s = "abcdcba", t = "abcdcba") == 14

assert Solution().longestPalindrome(s = "deified", t = "deified") == 14

assert Solution().longestPalindrome(s = "abracadabra", t = "abraccadabr") == 8

assert Solution().longestPalindrome(s = "longestpalindrome", t = "emordnilapgnol") == 20

assert Solution().longestPalindrome(s = "abcdefghijk", t = "kjihgfedcba") == 22

assert Solution().longestPalindrome(s = "abacax", t = "xacaba") == 12

assert Solution().longestPalindrome(s = "pqrstu", t = "utsrqponmlkjihgfedcba") == 12

assert Solution().longestPalindrome(s = "abcdef", t = "gfedcbaa") == 13

assert Solution().longestPalindrome(s = "civiccivic", t = "iviciciv") == 11

assert Solution().longestPalindrome(s = "aabbccdd", t = "ddeeccbbaa") == 14

assert Solution().longestPalindrome(s = "abcxyzdef", t = "fedxyzcba") == 7

assert Solution().longestPalindrome(s = "civic", t = "civiccivic") == 15

assert Solution().longestPalindrome(s = "banana", t = "nanaba") == 11

assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdfgdcaba") == 11

assert Solution().longestPalindrome(s = "tattarrattat", t = "tattarrattat") == 24

assert Solution().longestPalindrome(s = "level", t = "levvel") == 7

assert Solution().longestPalindrome(s = "xxyyyzzz", t = "zzzyyyxx") == 16

assert Solution().longestPalindrome(s = "rotorrotor", t = "rotor") == 15

assert Solution().longestPalindrome(s = "rotor", t = "rotator") == 7

assert Solution().longestPalindrome(s = "abacaxbaca", t = "xacabacaba") == 13

assert Solution().longestPalindrome(s = "mnopqrstu", t = "utsrqponmlkjihgfedcbazyxwvut") == 18

assert Solution().longestPalindrome(s = "aabbccddeeffgg", t = "ggffeeeeddccbbaa") == 22

assert Solution().longestPalindrome(s = "xyzyx", t = "yzyxxy") == 9

assert Solution().longestPalindrome(s = "aaaaaa", t = "bbbbbb") == 6

assert Solution().longestPalindrome(s = "abcdefg", t = "hijklmn") == 1

assert Solution().longestPalindrome(s = "abcdef", t = "fedcbag") == 12

assert Solution().longestPalindrome(s = "level", t = "leveleveleveleveleveleveleveleveleveleveleveleveleve") == 55

assert Solution().longestPalindrome(s = "abcdabcd", t = "dcbaabcd") == 9

assert Solution().longestPalindrome(s = "abcdeedcba", t = "fghijklkjihgf") == 13

assert Solution().longestPalindrome(s = "aaaabb", t = "aabbaa") == 10

assert Solution().longestPalindrome(s = "civic", t = "civic") == 10

assert Solution().longestPalindrome(s = "level", t = "levevl") == 8

assert Solution().longestPalindrome(s = "racecar", t = "madam") == 7

assert Solution().longestPalindrome(s = "deifieddeified", t = "deifiededeif") == 21

assert Solution().longestPalindrome(s = "noonhighnoon", t = "deifiedlevel") == 7

assert Solution().longestPalindrome(s = "abracadabra", t = "aracabradab") == 7

assert Solution().longestPalindrome(s = "level", t = "deified") == 7

assert Solution().longestPalindrome(s = "mirror", t = "rimmom") == 9

assert Solution().longestPalindrome(s = "abcdedcba", t = "zyxwxyzyx") == 9

assert Solution().longestPalindrome(s = "pneumonoultramicroscopicsilicovolcanoconiosis", t = "osivicnoclovosicrepimicroscopultramaounep") == 11

assert Solution().longestPalindrome(s = "xyzzyx", t = "abczyzyxcba") == 7

assert Solution().longestPalindrome(s = "abcxyzyxcba", t = "xyzzyx") == 11

assert Solution().longestPalindrome(s = "abcabcabc", t = "abcabcabc") == 3

assert Solution().longestPalindrome(s = "mississippi", t = "ppissimms") == 13

assert Solution().longestPalindrome(s = "abacaxaba", t = "abacaxaba") == 7

assert Solution().longestPalindrome(s = "hello", t = "olleh") == 10

assert Solution().longestPalindrome(s = "noonhighnoon", t = "noonlownoon") == 9

assert Solution().longestPalindrome(s = "abaccadda", t = "addacca") == 14

assert Solution().longestPalindrome(s = "refer", t = "repaper") == 7

assert Solution().longestPalindrome(s = "mississippi", t = "ippississimm") == 22

assert Solution().longestPalindrome(s = "abacaba", t = "bdcabdc") == 9

assert Solution().longestPalindrome(s = "mississippi", t = "noon") == 7

assert Solution().longestPalindrome(s = "noon", t = "noonnoonnoonnoon") == 20

assert Solution().longestPalindrome(s = "abracadabra", t = "abacabadabrac") == 11

assert Solution().longestPalindrome(s = "abcd", t = "abcdabcd") == 3

assert Solution().longestPalindrome(s = "abc", t = "mnopqr") == 1

assert Solution().longestPalindrome(s = "abccba", t = "xyzyx") == 6

assert Solution().longestPalindrome(s = "zzzzzz", t = "zzzzzz") == 12

assert Solution().longestPalindrome(s = "amanaplanacanalpanama", t = "amanaP lanac a nalp a namA") == 21

assert Solution().longestPalindrome(s = "noonnoon", t = "moonmoon") == 8

assert Solution().longestPalindrome(s = "noonhighnoon", t = "noon") == 9

assert Solution().longestPalindrome(s = "xyzz", t = "zzxy") == 4

assert Solution().longestPalindrome(s = "racecar", t = "civic") == 7

assert Solution().longestPalindrome(s = "mnopqr", t = "rqponm") == 12

assert Solution().longestPalindrome(s = "levellevellevel", t = "levevlevevlevevl") == 18

assert Solution().longestPalindrome(s = "mammam", t = "mammam") == 12

assert Solution().longestPalindrome(s = "kayak", t = "yakayk") == 7

assert Solution().longestPalindrome(s = "radar", t = "radar") == 10

assert Solution().longestPalindrome(s = "neveroddoreven", t = "levelmadamrotor") == 14

assert Solution().longestPalindrome(s = "madam", t = "refer") == 5

assert Solution().longestPalindrome(s = "hello", t = "ollehworld") == 10

assert Solution().longestPalindrome(s = "xyzuvw", t = "vwxyz") == 3

assert Solution().longestPalindrome(s = "zzzzzzzzzz", t = "zzzzzzzzzz") == 20

assert Solution().longestPalindrome(s = "zzzzz", t = "zzzz") == 9

assert Solution().longestPalindrome(s = "banana", t = "ananab") == 12

assert Solution().longestPalindrome(s = "abacabadabacaba", t = "abacabadabacaba") == 30

assert Solution().longestPalindrome(s = "rotor", t = "rotorrotorrotor") == 20

assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbbaa") == 24

assert Solution().longestPalindrome(s = "abracadabra", t = "arbadacarba") == 22

assert Solution().longestPalindrome(s = "aaaabbbb", t = "bbbbcccc") == 8

assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdgfdcaba") == 24

assert Solution().longestPalindrome(s = "repaper", t = "repaper") == 14

assert Solution().longestPalindrome(s = "aabbccddeeffgg", t = "ggffeeddcbaabbccddeeffgg") == 18

assert Solution().longestPalindrome(s = "racecar", t = "carrear") == 7

assert Solution().longestPalindrome(s = "abcabcabcabc", t = "cbacbacbacba") == 24

assert Solution().longestPalindrome(s = "racecar", t = "racecar") == 14

assert Solution().longestPalindrome(s = "aabbccdd", t = "dccbbaaa") == 15

assert Solution().longestPalindrome(s = "abcdefgfedcba", t = "ghijklimno") == 13

assert Solution().longestPalindrome(s = "aabbccddeeaabbccddeeaabb", t = "ddeeaabbccddeeaabb") == 6

assert Solution().longestPalindrome(s = "rotor", t = "rotor") == 10

Answer: assert Solution().longestPalindrome(s = "b", t = "aaaa") == 4

Answer: assert Solution().longestPalindrome(s = "hello", t = "world") == 3

Answer: assert Solution().longestPalindrome(s = "aaaa", t = "bbbb") == 4

Answer: assert Solution().longestPalindrome(s = "abcde", t = "ecdba") == 5

Answer: assert Solution().longestPalindrome(s = "noon", t = "moon") == 7

Answer: assert Solution().longestPalindrome(s = "race", t = "care") == 7

Answer: assert Solution().longestPalindrome(s = "a", t = "a") == 2

Answer: assert Solution().longestPalindrome(s = "abcd", t = "dcba") == 8

Answer: assert Solution().longestPalindrome(s = "xyz", t = "zyx") == 6

Answer: assert Solution().longestPalindrome(s = "abc", t = "def") == 1

Answer: assert Solution().longestPalindrome(s = "referrefer", t = "referref") == 16

Answer: assert Solution().longestPalindrome(s = "abccba", t = "abcba") == 7

Answer: assert Solution().longestPalindrome(s = "abcabc", t = "cbacba") == 12

Answer: assert Solution().longestPalindrome(s = "mnopqr", t = "rqpomn") == 8

Answer: assert Solution().longestPalindrome(s = "rotorrotor", t = "rotorrot") == 16

Answer: assert Solution().longestPalindrome(s = "madam", t = "madammadam") == 15

Answer: assert Solution().longestPalindrome(s = "aabbaabb", t = "bbaa") == 10

Answer: assert Solution().longestPalindrome(s = "aaaaabbbbb", t = "bbbbbbaaaa") == 19

Answer: assert Solution().longestPalindrome(s = "abccba", t = "bccbab") == 11

Answer: assert Solution().longestPalindrome(s = "aabbcc", t = "ccbbaa") == 12

Answer: assert Solution().longestPalindrome(s = "abcdef", t = "fedabc") == 6

Answer: assert Solution().longestPalindrome(s = "xyxyxy", t = "yxyxyx") == 12

Answer: assert Solution().longestPalindrome(s = "aba", t = "bab") == 5

Answer: assert Solution().longestPalindrome(s = "abcdefg", t = "gfedcba") == 14

Answer: assert Solution().longestPalindrome(s = "tatactatta", t = "tatattac") == 11

Answer: assert Solution().longestPalindrome(s = "madam", t = "madam") == 10

Answer: assert Solution().longestPalindrome(s = "aabaa", t = "bbabb") == 6

Answer: assert Solution().longestPalindrome(s = "abcdef", t = "fedcbaghi") == 12

Answer: assert Solution().longestPalindrome(s = "palindrome", t = "emordnilap") == 20

Answer: assert Solution().longestPalindrome(s = "xyzaaayzx", t = "zyxxzyxzy") == 9

Answer: assert Solution().longestPalindrome(s = "abcabcabc", t = "cbacbacba") == 18

Answer: assert Solution().longestPalindrome(s = "pqr", t = "rqp") == 6

Answer: assert Solution().longestPalindrome(s = "abcdcba", t = "abcdcba") == 14

Answer: assert Solution().longestPalindrome(s = "deified", t = "deified") == 14

Answer: assert Solution().longestPalindrome(s = "abracadabra", t = "abraccadabr") == 8

Answer: assert Solution().longestPalindrome(s = "longestpalindrome", t = "emordnilapgnol") == 20

Answer: assert Solution().longestPalindrome(s = "abcdefghijk", t = "kjihgfedcba") == 22

Answer: assert Solution().longestPalindrome(s = "abacax", t = "xacaba") == 12

Answer: assert Solution().longestPalindrome(s = "pqrstu", t = "utsrqponmlkjihgfedcba") == 12

Answer: assert Solution().longestPalindrome(s = "abcdef", t = "gfedcbaa") == 13

Answer: assert Solution().longestPalindrome(s = "civiccivic", t = "iviciciv") == 11

Answer: assert Solution().longestPalindrome(s = "aabbccdd", t = "ddeeccbbaa") == 14

Answer: assert Solution().longestPalindrome(s = "abcxyzdef", t = "fedxyzcba") == 7

Answer: assert Solution().longestPalindrome(s = "civic", t = "civiccivic") == 15

Answer: assert Solution().longestPalindrome(s = "banana", t = "nanaba") == 11

Answer: assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdfgdcaba") == 11

Answer: assert Solution().longestPalindrome(s = "tattarrattat", t = "tattarrattat") == 24

Answer: assert Solution().longestPalindrome(s = "level", t = "levvel") == 7

Answer: assert Solution().longestPalindrome(s = "xxyyyzzz", t = "zzzyyyxx") == 16

Answer: assert Solution().longestPalindrome(s = "rotorrotor", t = "rotor") == 15

Answer: assert Solution().longestPalindrome(s = "rotor", t = "rotator") == 7

Answer: assert Solution().longestPalindrome(s = "abacaxbaca", t = "xacabacaba") == 13

Answer: assert Solution().longestPalindrome(s = "mnopqrstu", t = "utsrqponmlkjihgfedcbazyxwvut") == 18

Answer: assert Solution().longestPalindrome(s = "aabbccddeeffgg", t = "ggffeeeeddccbbaa") == 22

Answer: assert Solution().longestPalindrome(s = "xyzyx", t = "yzyxxy") == 9

Answer: assert Solution().longestPalindrome(s = "aaaaaa", t = "bbbbbb") == 6

Answer: assert Solution().longestPalindrome(s = "abcdefg", t = "hijklmn") == 1

Answer: assert Solution().longestPalindrome(s = "abcdef", t = "fedcbag") == 12

Answer: assert Solution().longestPalindrome(s = "level", t = "leveleveleveleveleveleveleveleveleveleveleveleveleve") == 55

Answer: assert Solution().longestPalindrome(s = "abcdabcd", t = "dcbaabcd") == 9

Answer: assert Solution().longestPalindrome(s = "abcdeedcba", t = "fghijklkjihgf") == 13

Answer: assert Solution().longestPalindrome(s = "aaaabb", t = "aabbaa") == 10

Answer: assert Solution().longestPalindrome(s = "civic", t = "civic") == 10

Answer: assert Solution().longestPalindrome(s = "level", t = "levevl") == 8

Answer: assert Solution().longestPalindrome(s = "racecar", t = "madam") == 7

Answer: assert Solution().longestPalindrome(s = "deifieddeified", t = "deifiededeif") == 21

Answer: assert Solution().longestPalindrome(s = "noonhighnoon", t = "deifiedlevel") == 7

Answer: assert Solution().longestPalindrome(s = "abracadabra", t = "aracabradab") == 7

Answer: assert Solution().longestPalindrome(s = "level", t = "deified") == 7

Answer: assert Solution().longestPalindrome(s = "mirror", t = "rimmom") == 9

Answer: assert Solution().longestPalindrome(s = "abcdedcba", t = "zyxwxyzyx") == 9

Answer: assert Solution().longestPalindrome(s = "pneumonoultramicroscopicsilicovolcanoconiosis", t = "osivicnoclovosicrepimicroscopultramaounep") == 11

Answer: assert Solution().longestPalindrome(s = "xyzzyx", t = "abczyzyxcba") == 7

Answer: assert Solution().longestPalindrome(s = "abcxyzyxcba", t = "xyzzyx") == 11

Answer: assert Solution().longestPalindrome(s = "abcabcabc", t = "abcabcabc") == 3

Answer: assert Solution().longestPalindrome(s = "mississippi", t = "ppissimms") == 13

Answer: assert Solution().longestPalindrome(s = "abacaxaba", t = "abacaxaba") == 7

Answer: assert Solution().longestPalindrome(s = "hello", t = "olleh") == 10

Answer: assert Solution().longestPalindrome(s = "noonhighnoon", t = "noonlownoon") == 9

Answer: assert Solution().longestPalindrome(s = "abaccadda", t = "addacca") == 14

Answer: assert Solution().longestPalindrome(s = "refer", t = "repaper") == 7

Answer: assert Solution().longestPalindrome(s = "mississippi", t = "ippississimm") == 22

Answer: assert Solution().longestPalindrome(s = "abacaba", t = "bdcabdc") == 9

Answer: assert Solution().longestPalindrome(s = "mississippi", t = "noon") == 7

Answer: assert Solution().longestPalindrome(s = "noon", t = "noonnoonnoonnoon") == 20

Answer: assert Solution().longestPalindrome(s = "abracadabra", t = "abacabadabrac") == 11

Answer: assert Solution().longestPalindrome(s = "abcd", t = "abcdabcd") == 3

Answer: assert Solution().longestPalindrome(s = "abc", t = "mnopqr") == 1

Answer: assert Solution().longestPalindrome(s = "abccba", t = "xyzyx") == 6

Answer: assert Solution().longestPalindrome(s = "zzzzzz", t = "zzzzzz") == 12

Answer: assert Solution().longestPalindrome(s = "amanaplanacanalpanama", t = "amanaP lanac a nalp a namA") == 21

Answer: assert Solution().longestPalindrome(s = "noonnoon", t = "moonmoon") == 8

Answer: assert Solution().longestPalindrome(s = "noonhighnoon", t = "noon") == 9

Answer: assert Solution().longestPalindrome(s = "xyzz", t = "zzxy") == 4

Answer: assert Solution().longestPalindrome(s = "racecar", t = "civic") == 7

Answer: assert Solution().longestPalindrome(s = "mnopqr", t = "rqponm") == 12

Answer: assert Solution().longestPalindrome(s = "levellevellevel", t = "levevlevevlevevl") == 18

Answer: assert Solution().longestPalindrome(s = "mammam", t = "mammam") == 12

Answer: assert Solution().longestPalindrome(s = "kayak", t = "yakayk") == 7

Answer: assert Solution().longestPalindrome(s = "radar", t = "radar") == 10

Answer: assert Solution().longestPalindrome(s = "neveroddoreven", t = "levelmadamrotor") == 14

Answer: assert Solution().longestPalindrome(s = "madam", t = "refer") == 5

Answer: assert Solution().longestPalindrome(s = "hello", t = "ollehworld") == 10

Answer: assert Solution().longestPalindrome(s = "xyzuvw", t = "vwxyz") == 3

Answer: assert Solution().longestPalindrome(s = "zzzzzzzzzz", t = "zzzzzzzzzz") == 20

Answer: assert Solution().longestPalindrome(s = "zzzzz", t = "zzzz") == 9

Answer: assert Solution().longestPalindrome(s = "banana", t = "ananab") == 12

Answer: assert Solution().longestPalindrome(s = "abacabadabacaba", t = "abacabadabacaba") == 30

Answer: assert Solution().longestPalindrome(s = "rotor", t = "rotorrotorrotor") == 20

Answer: assert Solution().longestPalindrome(s = "aabbccddeeff", t = "ffeeddccbbaa") == 24

Answer: assert Solution().longestPalindrome(s = "abracadabra", t = "arbadacarba") == 22

Answer: assert Solution().longestPalindrome(s = "aaaabbbb", t = "bbbbcccc") == 8

Answer: assert Solution().longestPalindrome(s = "abacdfgdcaba", t = "abacdgfdcaba") == 24

Answer: assert Solution().longestPalindrome(s = "repaper", t = "repaper") == 14

Answer: assert Solution().longestPalindrome(s = "aabbccddeeffgg", t = "ggffeeddcbaabbccddeeffgg") == 18

Answer: assert Solution().longestPalindrome(s = "racecar", t = "carrear") == 7

Answer: assert Solution().longestPalindrome(s = "abcabcabcabc", t = "cbacbacbacba") == 24

Answer: assert Solution().longestPalindrome(s = "racecar", t = "racecar") == 14

Answer: assert Solution().longestPalindrome(s = "aabbccdd", t = "dccbbaaa") == 15

Answer: assert Solution().longestPalindrome(s = "abcdefgfedcba", t = "ghijklimno") == 13

Answer: assert Solution().longestPalindrome(s = "aabbccddeeaabbccddeeaabb", t = "ddeeaabbccddeeaabb") == 6

Answer: assert Solution().longestPalindrome(s = "rotor", t = "rotor") == 10

import random
import functools
import collections
import string
import math
import datetime

from typing import *
from functools import *
from collections import *
from itertools import *
from heapq import *
from bisect import *
from string import *
from operator import *
from math import *

inf = float('inf')

class ListNode:
    def __init__(self, val=0, next=None):
        self.val = val
        self.next = next

def list_node(values: list):
    if not values:
        return None
    head = ListNode(values[0])
    p = head
    for val in values[1:]:
        node = ListNode(val)
        p.next = node
        p = node
    return head

def is_same_list(p1, p2):
    if p1 is None and p2 is None:
        return True
    if not p1 or not p2:
        return False
    return p1.val == p2.val and is_same_list(p1.next, p2.next)

class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right

def tree_node(values: list):
    if not values:
        return None
    root = TreeNode(values[0])
    i = 1
    queue = deque()
    queue.append(root)
    while queue:
        node = queue.popleft()
        if i < len(values) and values[i] is not None:
            node.left = TreeNode(values[i])
            queue.append(node.left)
        i += 1
        if i < len(values) and values[i] is not None:
            node.right = TreeNode(values[i])
            queue.append(node.right)
        i += 1
    return root

def is_same_tree(p, q):
    if not p and not q:
        return True
    elif not p or not q:
        return False
    elif p.val != q.val:
        return False
    else:
        return is_same_tree(p.left, q.left) and is_same_tree(p.right, q.right)

class Solution:
    def calc(self, s: str, t: str) -> int:
        n, m = len(s), len(t)
        f = [[0] * (m + 1) for _ in range(n + 1)]
        for i, x in enumerate(s):
            for j, y in enumerate(t):
                if x == y:
                    f[i + 1][j] = f[i][j + 1] + 1
        mx = list(map(max, f))
        ans = max(mx) * 2  # |x| = |y| 的情况

        # 计算 |x| > |y| 的情况，中心扩展法
        for i in range(2 * n - 1):
            l, r = i // 2, (i + 1) // 2
            while l >= 0 and r < n and s[l] == s[r]:
                l -= 1
                r += 1
            if l + 1 <= r - 1:  # s[l+1] 到 s[r-1] 是非空回文串
                ans = max(ans, r - l - 1 + mx[l + 1] * 2)
        return ans

    def longestPalindrome(self, s: str, t: str) -> int:
        return max(self.calc(s, t), self.calc(t[::-1], s[::-1]))