B. Queue at the School Solution

#include<bits/stdc++.h>

using namespace std;

int main()

{

    int n,t,i;

    char s[55],temp ;

    cin>>n>>t>>s;

    while(t--){

        for(i=0;i<n;i++){

        if (s[i]=='B' && s[i+1]=='G'){

            temp=s[i];

            s[i]=s[i+1];

            s[i+1]=temp;

            i++;

        }

    }

    }

    cout<<s<<endl;

}