#include<bits/stdc++.h>
using namespace std;
bool check(int x)
{
	int fu=x,count=0;
	while(fu!=0)
	{
		count+=1;
		fu/=10;
	} 
//	cout << "count" << count << endl;
	bool found[count];
	memset(found,false,count);
	while(x!=0)
	{
		int wei=x%10;
		if(found[wei]==true||wei>=count)
			return false; 
		else if(found[wei]==false)
			found[wei]=true;
		x/=10;
	}
	for(int i=0;i<count;i++)
	{
//		cout << count << endl;
		if(found[i]==false)
			return false;
	}
	return true;
}
int main()
{
	int n,m;
	cin >> n >> m;
	int ans=0;
	for(int i=n;i<=m;i++)
	{
		if(check(i)==true)
		{
//			cout << i << " ";
			ans+=1; 
		}
	}
	cout << ans << endl;
	return 0;
}