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

int x[12], ans;

bool s(int n)
{
	int n1 = n, cnt = 0;
	while (n1)
	{
		x[n1 % 10]++;
		cnt++;
		n1 /= 10;
	}
	bool flag = 1;
	for (int i = 0; i < cnt; i++)
	{
		if (x[i] != 1) 
		{
			flag = 0;
			break;
		 } 
	}
	return flag;
}

int main()
{
	int a, b;
	cin >> a >> b;
	for (int i = a; i <= b; i++)
	{
		memset(x, 0, sizeof(x));
		if (s(i))
		{
			ans++;	
		 } 
	}
	cout << ans;
	return 0;
 }