#include <bits/stdc++.h>
using namespace std;
int flag[11];
bool func(int x)
{
	int cnt = 0;
	for (int i = 0; i <= 9; ++i) flag[i] = 0;
	while (x)
	{
		flag[x % 10]++;
		if (flag[x % 10] >= 2) return 0;
		x /= 10;
		cnt++;
	}
	for (int i = 0; i <= 9; ++i)
	{
		if (flag[i] != 1 && cnt > i) return 0;
		if (flag[i] != 0 && cnt <= i) return 0;
	}
	return 1;
}
int main()
{
	int a, b, sum = 0;
	cin >> a >> b;
	for (int i = a; i <= b; ++i)
	{
		if (func(i)) sum++;
	}
	cout << sum << endl;
	return 0;
}