#include<bits/stdc++.h>
using namespace std;
int a,b;
int ans;
int check(int x){
	int ws=0;
	int a[10];
	memset(a,0,sizeof(a));
	if(x==0) ws=1,a[0]=1;
	while(x){
		a[x%10]++;
		x/=10;
		ws++;
	}
	int sum=0;
	for(int i=0;i<ws;i++)if(a[i])sum++;
	return sum==ws;
} 
int main(){
	cin>>a>>b;
	for(int i=a;i<=b;i++) ans+=check(i);
	cout<<ans<<endl;
	return 0;
}