#include <bits/stdc++.h>   using namespace std;   int main() {     string s;     cin >> s;     s =  *  + s;     int add = 0;     int n = (s.length()) - 1;     for (int i = 1; i + i <= n; i++) {       if (s[i] != s[s.size() - i]) {         add++;       }     }     if (add <= 1 && (n & 1) || add == 1)       cout <<  YES n ;     else       cout <<  NO n ;   }   