#include <bits/stdc++.h>
using namespace std;
const long double PI = atan(1.0) * 4.0;
const long long int MOD = 1e9 + 7;
const long long int INF = 1e18;
const long double EPS = 0.0000001;
int main() {
  ios_base::sync_with_stdio(false), cin.tie(NULL);
  int n, k;
  cin >> n >> k;
  string s;
  cin >> s;
  map<char, int> a;
  for (int i = 0; i < n; i++) a[s[i]]++;
  int j = 97;
  while (k != 0 && j <= 122) {
    for (int i = 0; i < n; i++) {
      if (s[i] == char(j)) {
        s[i] = '*';
        k--;
        if (k == 0) break;
      }
    }
    j++;
  }
  for (int i = 0; i < n; i++) {
    if (s[i] != '*') cout << s[i];
  }
  return 0;
}
