#include <bits/stdc++.h>
#define ll long long
using namespace std;

int a[15];
int main()
{
	int x,b;
	cin >> x >> b;
	int cnt = 0;
	for(int i = x;i <= b;i++)
	{
		for(int i = 0;i <= 10;i++)
		{
			a[i] = 0;
		}
		int t = i;
		int g = 0;
		while(t)
		{
			a[t % 10]++;
			t /= 10;
			g++;
		}
		int f = 1;
		for(int i = 0;i < g;i++)
		{
			if(a[i] != 1)
			{
				f = 0;
				break;
			}
		}
		if(f == 1)
		{
			cnt++;
		}
	}
	cout << cnt;
	return 0;
}