def f(L):
    N = len(L)
    temp = [None] * N
    for i in range(N):
        temp[i] = L[N - 1 - i]
    return L == temp

S = list(input())
M = len(S)
dp = [1] * M
for i in range(1, M):
    for j in range(i):
        if f(S[j+1:i+1]):
            dp[i] = max(dp[i], dp[j], i - j)
            if f(S[:j + 1]):
                dp[i] = max(dp[i], j + 1)
print(dp[-1])