Problem: You are given a string t consisting of n lowercase Latin letters and an integer number k.

Let's define a substring of some string s with indices from l to r as s[l ... r].

Your task is to construct such string s of minimum possible length that there are exactly k positions i such that s[i ... i + n - 1] = t. In other words, your task is to construct such string s of minimum possible length that there are exactly k substrings of s equal to t.

It is guaranteed that the answer is always unique.

Input

The first line of the input contains two integers n and k (1 ≤ n, k ≤ 50) — the length of the string t and the number of substrings.

The second line of the input contains the string t consisting of exactly n lowercase Latin letters.

Output

Print such string s of minimum possible length that there are exactly k substrings of s equal to t.

It is guaranteed that the answer is always unique.

Examples

Input

3 4
aba


Output

ababababa


Input

3 2
cat


Output

catcat

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
vector<size_t> prefix_function(string s) {
  size_t n = (int)s.length();
  vector<size_t> pi(n);
  for (int i = 1; i < n; ++i) {
    size_t j = pi[i - 1];
    while (j > 0 && s[i] != s[j]) j = pi[j - 1];
    if (s[i] == s[j]) ++j;
    pi[i] = j;
  }
  return pi;
}
int main(int argc, char* argv[]) {
  size_t n, k;
  string t;
  cin >> n >> k >> t;
  size_t s = prefix_function(t)[t.size() - 1];
  stringstream ss;
  ss << t;
  --k;
  string new_t = t.substr(s, t.size() - s);
  for (size_t i = 0; i < k; ++i) {
    ss << new_t;
  }
  cout << ss.str() << endl;
  return 0;
}