func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     cin.sync_with_stdio(false), cin.tie(nullptr);     int tests;     cin >> tests;     while (tests--) {       int n, k;       string s;       cin >> n >> k >> s;       const int need = n / k;       vector<vector<int>> counts(k, vector<int>(26, 0));       for (int i = 0; i < n; i++) {         counts[i % k][s[i] -  a ]++;       }       int ans = 0;       for (int i = 0, j = k - 1; i <= j; i++, j--) {         int cost = need * 2 - counts[i][0] - counts[j][0];         for (int c = 1; c < 26; c++) {           cost = min(cost, need * 2 - counts[i][c] - counts[j][c]);         }         ans += (i == j ? cost / 2 : cost);       }       cout << ans <<   n ;     }   }   