#include <bits/stdc++.h>
using namespace std;
char a[55];
int main() {
  int n, i, j, k, ans, x;
  int len;
  while (cin >> a) {
    ans = 0;
    x = 0;
    len = strlen(a);
    for (i = 0; i < len; i++) {
      for (j = len - 1; j > i; j--) {
        for (k = i; k <= j; k++) {
          if (a[k] != a[j - k + i]) break;
        }
        if (k != j + 1) {
          ans = max(ans, j - i);
        }
      }
    }
    if (ans != 0)
      cout << ans + 1 << endl;
    else
      cout << "0" << endl;
  }
  return 0;
}
