#include <bits/stdc++.h>

using namespace std;
#define int long long

int32_t main() {
	int a, b;
	cin >> a >> b;

	if(a >= 10) {
		cout << 0 << endl;
	} else {
		int total = 0;

		string digs = to_string(b);

		int pw = 1;
		for(int i = 1; i < digs.size(); ++i) {
			pw *= (9 - a + 1);
			total += pw;
		}

		cerr << total << endl;

		for(int i = 0; i < digs.size(); ++i) {
			int dig = digs[i] - '0';
			if(dig < a) break;

			// now dig >= a
			int add = 1;
			for(int j = i + 1; j < digs.size(); ++j) {
				add *= (9 - a + 1);
			}
			add *= (dig - a);

			total += add;	
		}

		cout << total << endl;
	}


	return 0;
}