#include<bits/stdc++.h>
typedef long long ll;
using namespace std;
int INF = 1e9;
int MOD = 1e9+7;
main(){
    string s;
    int maxlen = 1;
    cin >> s;
    for(int i = 0;i < s.length()-1;i++){
        for(int j = i+1;j < s.length();j++){
            if(i+(j-i)*2 > s.length())break;
            string sub = s.substr(i,j-i);
            reverse(sub.begin(),sub.end());
            if(sub == s.substr(j,j-i)&&
            s.length() != (j-i)*2){
                maxlen = max(maxlen,(j-i)*2);
            }
            if(i+(j-i)*2 >= s.length())continue;
            if(sub == s.substr(j+1,j-i) &&
            s.length() != (j-i)*2+1){
                maxlen = max(maxlen,(j-i)*2+1);
            }
        }
    }
    cout << maxlen << endl;
}