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

int main() {
  int N, K;
  string S;
  deque<char> d;
  cin >> N >> K >> S;

  for (char c : S)
    d.push_back(c);
  
  for (int i = 0; i < K - 1; i++) {
    d.push_back(d.front());
    d.pop_front();
  }

  for (char c : d)
    cout << c;
  cout << endl;
}