def kaibun(S):
    n = len(S)
    S = list(S)
    kaibun = []
    for i in range(n):
        s = S[i]
        for j in range(i + 1, n):
            if (i == 0) and (j == n - 1):
                break
            s += S[j]
            s_rev = ''
            for k in range(1, len(s) + 1):
                s_rev += s[-k]
            if s == s_rev:
                kaibun.append(len(s))
    if len(kaibun) == 0:
        return 1
    else:
        ans = max(kaibun)
        return ans

def main():
    S = input()
    print(kaibun(S))

if __name__ == '__main__':
    main()