#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

int main() {
    int n,k;
    string s;
    cin >> n >> k >> s;
    
    string ans;
    for (int i=k-1; i<n; i++) ans += s[i];
    for (int i=0; i<k-1; i++) ans += s[i];
    cout << ans << endl;
}