#include<bits/stdc++.h>
using namespace std;
int pd(int a){
	int b[12]={0,0,0,0,0,0,0,0,0,0},w=0;
	while(a){
		w++;
		b[a%10]++;
		a/=10;
	}
	for(int i=0;i<=9;i++)if(b[i]!=1&&i<w||b[i]>=1&&i>=w)return 0;
	return 1;
}
int main(){
	int a,b,ans=0;
	cin>>a>>b;
	for(int i=a;i<=b;i++)if(pd(i))ans++;
	cout<<ans<<endl;
	return 0;
}