#include<bits/stdc++.h>
using namespace std;
long long a,b,z[20]={0},s=1,sum=0,as=0,i;
int main(){
	cin>>a>>b;
	for(int q=a;q<=b;q+=1)
	{	i=q;
		sum=0;
		s=1;
		long long z[20]={0};
		while(1)
		{	 
		z[i%10]++;
		if(i/10<1)
		break;
			i/=10;
			s+=1;
		}
		
			for(int j=0;j<s;j+=1)
				if(z[j]==1)
				sum+=1;
			if(sum==s)
			{
			as=as+1;	
				}
	
		}
cout<<as;
return 0;
}