#include <bits/stdc++.h>
using namespace std;
int cnt = 0;
bool f(int x)
{
	int l = x, c = 0;
	while (l != 0)
	{
		c++;
		l /= 10;
	}
	int a[c] = {0};
	int ge;
	l = x;
	while (l != 0)
	{
		ge = l % 10;
		a[ge]++;
		l /= 10;
	}
	for (int i = 0; i < c; i++)
	{
		if (a[i] != 1)
		{
			return false;
		}
	}
	return true;
}
int main()
{
	int a, b;
	cin >> a >> b;
	for (int i = a; i <= b; i++)
	{
		if (f(i))
		{
			cnt++; 
		} 
	}
	cout << cnt << endl;
	return 0;
}