#include <bits/stdc++.h>
using namespace std;
using UL = unsigned long int;
using UI = unsigned int;
using ULL = unsigned long long int;
using LI = long int;
using LL = long long;
using LF = double;
using LLF = long double;
const int mod1 = 1000000007;
const int mod2 = 998244353;
const double PI = acos(-1);
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
  int ntc = 1, tc, i, j;
  int n, k;
  for (tc = 1; tc <= ntc; tc++) {
    cin >> n >> k;
    string s;
    cin >> s;
    int cnt1[26] = {0}, cnt2[26] = {0};
    string ans = "";
    for (auto ch : s) {
      cnt1[ch - 'a']++;
    }
    for (i = 0; i < 26 && k > 0; i++) {
      cnt2[i] += min(k, cnt1[i]);
      k -= min(k, cnt1[i]);
    }
    for (auto ch : s) {
      if (cnt2[ch - 'a'] > 0) {
        cnt2[ch - 'a']--;
        continue;
      }
      cout << ch;
    }
  }
  return 0;
}
