#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>

#define FORR(i,b,e) for(int i=(b);i<(int)(e);++i)
#define FOR(i,e) FORR(i,0,e)
#define ALL(c) begin(c), end(c)
#define dump(var) cerr << #var ": " << var << "\n"
#define dumpc(con) for(auto& e: con) cerr << e << " "; cerr<<"\n"

using namespace std;

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    string S;
    while (cin >> S) {
        int t1 = 1, t2 = 1;
        FOR(i, S.size()) {
            for (int j = S.size()-1; j > i; j--) {
                bool palin = true;
                for (int k = 0, l = (i+j)/2; palin && (i+k) <= l; k++) {
                    if (S[i+k] != S[j-k]) {
                        palin = false;
                    }
                }
                if (palin) {
                    int size = j-i+1;
                    if (t1 < size) {
                        t2 = t1; t1 = size;
                    }
                    else if (t2 < size) {
                        t2 = size;
                    }
                }
                
            }
        }
        if (t1 == S.size()) {
            cout << t2 << endl;
        }
        else {
            cout << t1 << endl;
        }
    }
    return 0;
}