#include <bits/stdc++.h>

using namespace std;
using ll = long long;

//R[2n]...n文字目を中心とする最長回文長
//R[2n+1]...n文字目とn+1文字目を中心とする最長回文長
template <typename T>
vector<int> manacher(T &s){
    string S="";
    for (auto x : s){
        S += x;
        S += '$';
    }
    S.pop_back();
    vector<int> R(S.size());
    int i=0, j=0;
    while(i < S.size()){
        while(i-j >= 0 && i+j < S.size() && S[i-j] == S[i+j]) j++;
        R[i] = j;
        int k=1;
        while(i-k >= 0 && k + R[i-k] < j){
            R[i+k] = R[i-k];
            k++;
        }
        i += k;
        j -= k;
    }

    for (int i=0; i<S.size(); i++){
        if (i % 2 == R[i] % 2) R[i]--;
    }

    return R;
}

int main(){

    string S;
    cin >> S;
    int N = S.size();
    vector<int> dp(N+1), R = manacher(S);
    dp[0] = 1e9;
    for (int i=1; i<=N; i++){
        for (int j=1; j<=N; j++){
            if (R[i+j-2] >= i-j+1){
                dp[i] = max(dp[i], min(dp[j-1], i-j+1));
            }
        }
    }

    cout << dp[N] << endl;

    return 0;
}