#include<bits/stdc++.h>
using namespace std;
int a,b,ans;
int main(){
	cin>>a>>b;
	for(int i=a;i<=b;i++){
		string s=to_string(i);
		int jl[15]={0,0,0,0,0,0,0,0,0,0};
		bool flag=true;
		for(int j=0;j<s.size();j++){
			if(jl[s[j]-'0']==1 || s[j]-'0'>=s.size()){
				flag=false;
				break;
			}
			else jl[s[j]-'0']=1;
		}
		ans+=flag;
	}
	cout<<ans;
	return 0;
}