#include <iostream>
#include <iomanip>
#include <cmath>


using namespace std;

int main() {
    ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
    int n, k;
    cin >> n >> k;
    char arr[n];
    int freq[125]={};
    if (n==k) {
        cout << endl;
        return 0;
    }
    for (int i=0; i<n; i++) {
        cin >> arr[i];
        freq[arr[i]]++;
    }
    for (int i=97; i<123; i++) {
        while(k>0 && freq[i]>0) {
            freq[i]--;
            k--;
        }
        if(k==0) break;
    }
    string s;
    s = "";
    for (int i=n-1; i>=0; i--) {
        if(freq[arr[i]]>0) {
            freq[arr[i]]--;
            s.insert(s.begin(), arr[i]);
        }
    }
    cout << s;
    return 0;
}