#include <bits/stdc++.h>

using namespace std;

bool k[1000010];

bool check(int n)
{
	int t = n , cnt = -1 , i = 0;
	while (t)
	{
		t /= 10;
		cnt++;
		k[i++] = 0;
	}
	t = n;
	while (t)
	{
		int ge = t % 10;
		t /= 10;
		if (ge > cnt) return false;
		if (k[ge] == 1) return false;
		k[ge] = 1;
	}
	return true;
}

int main()
{
	int a , b , cnt = 0;
	cin >> a >> b;
	for (int i = a ; i <= b ; i++)
	{
		if (check(i))
		{
			cnt++;
		}
	}
	cout << cnt;
	return 0;
}