#include <iostream>
#include <vector>

using namespace std;

int v[30];

int main() {
    //freopen("c.in", "r", stdin);
    //freopen("c.out", "w", stdout);
    unsigned long long a, b;
    cin >> a >> b;
    if (a > 9) {
        cout << "0\n";
        return 0;
    }
    unsigned long long answer = 0, howMany = 1, power10 = 10, digits = 9 - a + 1;
    for (int i = 1; power10 <= b; power10 *= 10LL, i++) {
        howMany *= digits;
        answer += howMany;
    }
    howMany = 1;
    while (b) {
        v[0]++;
        v[v[0]] = b % 10;
        b /= 10;
        howMany *= digits;
    }
    howMany /= digits;
    for (int i = v[0]; i >= 1; i--) {
        if (v[i] >= a)
            answer += howMany * (v[i] - a);
        else
            break;
        howMany /= digits;
    }
    cout << answer << "\n";
    return 0;
}