#include<iostream>
#include<string>
#include<cstring>
#include<iomanip>
#include<algorithm>
#include<cmath>
#define ll long long
using namespace std;
ll n,k,id[9999999],head,tail,a[9999999];
int main(){
    cin>>n>>k;
    for(int i=1;i<=n;i++){
        char c;
        cin>>c;
        a[i]=c-'0';
    }
    tail=k;
    for(int i=1;i<=k;i++){
        ll id1=0;
        a[0]=999999999;
        for(int j=1;j<=n;j++){
            if(a[i]<a[id1])id1=i;
        }
        id[++head]=id1;
    }
    for(int i=1;i<=n;i++){
        bool kkk=0;
        for(int j=1;j<=tail;j++){
            if(id[j]==i){
                kkk=1;
                break;
            }
        }
        if(!kkk)cout<<a[i];
    }
    return 0;
}