266B.Queue_at_the_School.cpp

#include <bits/stdc++.h>
using namespace std;

int main()
{
    int n, t;
    string s;
    cin >> n >> t>> s;

    while(t--){
        for(int i=1; i<n; i++){
            if(s[i] == 'G' && s[i-1] == 'B'){
                s[i] = 'B';
                s[i-1] = 'G';
                i++;

            }
        }
    }
    cout<<s;
return 0;
}