#include <bits/stdc++.h>
using namespace std;
const long long int N = 1e5 + 7, mod = 1e9 + 7;
struct Comp {
  bool operator()(pair<long long int, long long int> p, long long int s) const {
    return p.first < s;
  }
  bool operator()(long long int s, pair<long long int, long long int> p) const {
    return s < p.first;
  }
};
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long int n, k;
  cin >> n >> k;
  string s;
  cin >> s;
  long long int arr[26] = {0}, res[26] = {0};
  for (long long int i = 0; i < n; i++) {
    arr[s[i] - 'a']++;
  }
  for (long long int i = 0; i < 26; i++) {
    if (arr[i] > k) {
      res[i] = k;
      break;
    } else
      res[i] = arr[i];
    k -= arr[i];
  }
  for (long long int i = 0; i < n; i++) {
    if (res[s[i] - 'a']) {
      res[s[i] - 'a']--;
      continue;
    }
    cout << s[i];
  }
}
