#include<bits/stdc++.h>

using namespace std;

bool fa[15];

signed main() {
	int a, b;
	cin >> a >> b;
	int ans = 0;
	for (int i = a; i <= b; i++) {
		int ci = i;
		bool ok = true;
		int ff = 0;
		memset(fa, 0, sizeof(fa));
		while (ci) {
			ok &= !fa[ci % 10];
			fa[ci % 10] = true;
			ci /= 10;
			ff++;
		}
		ci = i;
		while (ci) {
			ok &= ci % 10 < ff;
			ci /= 10;
		}
		ans += ok;
	}
	cout << ans;
}