#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  long long int n;
  long long int k;
  string s;
  cin >> n;
  cin >> k;
  cin >> s;
  long long int arr[27];
  memset(arr, 0, sizeof(arr));
  for (int i = 0; i < n; i++) {
    int x = s[i] - 'a';
    arr[x]++;
  }
  for (int i = 0; i < 26; i++) {
    if (arr[i] > 0 && k > 0) {
      if (arr[i] >= k) {
        arr[i] = k;
        k = 0;
      } else
        k = k - arr[i];
    } else if (k == 0)
      arr[i] = 0;
  }
  for (int i = 0; i < n; i++) {
    int a = s[i] - 'a';
    if (arr[a] > 0)
      arr[a]--;
    else
      cout << s[i];
  }
  return 0;
}
