#include <iostream>
#include <cmath>
using namespace std;
bool isLuck(int n){
	int digits=floor(log10(n))+1;
	int d;
	//²»°üÀ¨£¨Î»Êý-1£©ÒÔÉϵÄÊý×Ö
	//ÿ¸öÊý×Ö²»Öظ´
	bool e[10]={0,0,0,0,0,0,0,0,0,0};
	while(n>0){
		d=n%10;
		n/=10;
		if(d>digits-1){
			return 0;
		}
		if(e[d]){
			return 0;
		}
		e[d]=1;
	}
	return 1;
}
int main(){
	int a,b;
	int cnt=0;
	cin>>a>>b;
	for(int i=a;i<=b;i++){
		if(isLuck(i)){
			cnt++;
		}
	}
	cout<<cnt;
	return 0;
}