#include <bits/stdc++.h>   using namespace std;   const int maxn = 2e5 + 7;   const int inf = 0x3f3f3f;   char s[maxn];   char str[4] =  RGB ;   int main() {     int q;     scanf( %d , &q);     while (q--) {       int n, m;       scanf( %d%d , &n, &m);       scanf( %s , s);       int minn = inf;       n -= m;       for (int i = 0; i <= n; i++) {         for (int j = 0; j < 3; j++) {           int jishu = 0, temp;           temp = (j <= 1 ? j : 2);           for (int k = 0; k < m; k++) {             if (s[i + k] != str[(temp + k) % 3]) {               jishu++;             }           }           minn = min(minn, jishu);         }       }       printf( %d n , minn);     }   }   