func_code_string: #include <bits/stdc++.h>   #pragma comment(linker,  /STACK:102400000,102400000 )   const int inf = 0x3f3f3f3f;   const long double PI = acos(-1);   using namespace std;   const int N = 1e5 + 10;   int t, n, ans;   char s[N];   int solve() {     for (char c =  a ; c <=  z ; c++) {       int temp = 0, i = 0, j = n - 1;       while (i < j) {         if (s[i] != s[j]) {           if (s[i] == c) {             i++, temp++;           } else if (s[j] == c) {             j--, temp++;           } else {             temp = n + 1;             break;           }         } else {           i++, j--;         }       }       ans = min(ans, temp);     }     if (ans == n + 1)       return -1;     else       return ans;   }   int main() {     ios::sync_with_stdio(false), cin.tie(0);     cin >> t;     while (t--) {       cin >> n;       for (int i = 0; i < n; i++) cin >> s[i];       ans = inf;       cout << solve() << endl;     }   }   