题解 | #密码截取#
密码截取
https://www.nowcoder.com/practice/3cd4621963e8454594f00199f4536bb1
# 你能帮Catcher找出最长的有效密码串吗？找出最长的对称字串
# ABBA 4
# ABBBA 5
# 12HHHHA 4
#对称的密码
s = input()
ls= []
for i in range(len(s)-1):
for j in range(len(s)-1,i,-1):
if s[i] == s[j] and s[i+1:j] == s[j-1:i:-1]:
ls.append(j-i+1)
break
print(max(ls))