#include <bits/stdc++.h>
using namespace std;
int N,K;
pair<vector<int>,int> f(int n, int k, vector<int> &S, int x){
    if(n == k) return {S,x};
    vector<int> A={};
    int now = 0;
    for(int i=0;i<S.size();i++){
        if(i != 0) now++;
        if(S[i] == 1) continue;
        if(S[i] != 1 && (x+i)%2 == 1){
            if(now != 0) A.push_back(now);
            A.push_back(S[i]-1);
            now = 0;
        }
        else now += S[i]-1;
    }
    if(now != 0) A.push_back(now);
    return {A,1-(S[0] > 1 && x == 1)};
}
int main(){
  cin>>N>>K;
  vector<int> S={};
  for(int i=0;i<N;i++){
      char a;
      cin>>a;
      S.push_back(a-'0');
  }
  vector<int> T={};
  int now = 1;
  for(int i=1;i<N;i++){
      if(S[i] != S[i-1]){
          T.push_back(now);
          now=1;
      }
      else now++;
  }
  T.push_back(now);
  int a=S[0];
  for(int i=N;i>K;i--){
      pair<vector<int>,int> z = f(i,K,T,a);
      tie(T,a) = z;
  }
  for(int i=0;i<T.size();i++){
      for(int j=0;j<T[i];j++) cout<<(a+i)%2;
  }
  cout<<endl;
}