题解 | #最长回文子串#

def len_max(a):
    i=0
    max_len=1
    while i<len(a):
        j=len(a)-1
        while i<=j:
            if  a[i]==a[j] and a[i:j+1]==''.join(list(reversed(a[i:j+1]))):
                max_len=max(max_len,j-i+1)
                break
            j-=1
        i+=1
    return max_len
while True:
    try:
        s=input()
        max_len=len_max(s)
        print(max_len)
    except:
        break