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

bool f(int n)
{
	int a[11] = {}, x = 0;
	while(n)
	{
		int d = n % 10;
		a[d]++;
		x++;
		n /= 10;
	}
	int cnt = 0;
	for(int i = 0; i < 10; i++)
	{
		if(a[0] == 1 && a[i] == 1 && a[i + 1] == 1)
		{
			cnt++;
		}
	}
	if(a[x - 1] == 1)
	{
		cnt++;
	}
	return cnt == x;
}
int main()
{
	int a, b;
	cin >> a >> b;
	int cnt = 0;
	for(int i = a; i <= b; i++)
	{
		if(f(i))
		{
			cnt++;
		}
	}
	cout << cnt << endl;
	return 0;
}