#include<bits/stdc++.h>
using namespace std;
int main(){
	int a,b,ans=0;
	cin>>a>>b;
	for(int i=a;i<=b;i++)
	{
		int x=i,y=0,tot=0;
		while(x>0)
		{
			x/=10;
			y++;
		}
		for(int j=0;j<=y-1;j++)
		{
			int s=i,t=0;
			while(s>0)
			{
				int k=s%10;
				s/=10;
				if(k==j)
				{
					t=1;
				}
			}
			if(t==0)
			{
				tot=1;
				break;
			}
		}
		if(tot==0) ans++;
	}
	cout<<ans;
	return 0;
}