#include<bits/stdc++.h>
using namespace std;
const int N=2e6+5;
int n,k,f[N];
int main(){
	freopen("whz_number.in","r",stdin);
	freopen("whz_number.out","w",stdout);
	ios::sync_with_stdio(0);
	cin.tie(0);cout.tie(0);
	while(cin>>n>>k){
		memset(f,0,sizeof(f));
		bool isc=false;
		for(int i=n;i>=1;i--){
			int res=i,ans=0;
			while(res){
				if(res%10==0) ans++;
				res/=10;
			} 
			f[i]=f[i+1]+ans;
			if(f[i]==k){
				isc=true;
				cout<<i<<"\n";
				break;
			}
		}
		if(isc) continue;
		f[0]=f[1]+1;
		if(f[0]==k){
			cout<<0<<"\n";
		}
	}
	return 0;
}