#include <bits/stdc++.h>
using namespace std;
int n, m;

int main() {
	freopen("whz_number.in", "r", stdin);
	freopen("whz_number.out", "w", stdout);
	unsigned long long k;
	while (cin >> n >> k) {
		unsigned long long cnt = 0;
		for (int i = n; i >= 0; i--) {
			int tmp = i;
			while (tmp != 0) {
				if (tmp % 10 == 0)
					cnt++;
				tmp /= 10;
			}
			if (cnt == k) {
				cout << i << endl;
				break;
			}
			if (i == 0 && cnt <= k) {
				cout << 0 << endl;
				break;
			}
		}
	}
	return 0;
}