题解 | #最长回文子串#

import sys
for line in sys.stdin.readlines():
    line = line.strip()
    length = len(line)
    ret = 1
    for i in range(1, length - 1):
        left = i - 1
        right = i + 1
        while line[i] == line[left] and left >= 0:
            left -= 1
        while line[i] == line[right] and right < length:
            right -= 1
        while (left >= 0 and right < length and line[left] == line[right]):
            left -= 1
            right += 1
        ret = max(right - left - 1, ret)
    print(ret)