func_code_string: #include <bits/stdc++.h>   using namespace std;   int main(int argc, char const *argv[]) {     int cases;     cin >> cases;     while (cases--) {       int length, target;       cin >> length >> target;       vector<vector<int>> BGR(3, vector<int>(length, 0));       string inp;       cin >> inp;       for (size_t i = 0, tok; i < inp.length(); ++i) {         if (inp[i] ==  B )           tok = 0;         else if (inp[i] ==  G )           tok = 1;         else           tok = 2;         BGR[(tok + i) % 3][i] = 1;       }       int ans = target;       for (auto x : BGR) {         size_t j = 0;         int init = target;         for (; j < target; ++j) init -= x[j];         ans = init < ans ? init : ans;         for (size_t i = 0; j < x.size(); ++i, ++j) {           init += x[i] - x[j];           ans = init < ans ? init : ans;         }       }       cout << ans <<   n ;     }     return 0;   }   