#include <bits/stdc++.h>

using namespace std;

#define int long long

bool f(int a){
	int t = 0;
	while(pow(10,t) <= a){
		++t;
	}
	int s[t];
	for(int i = 0;i < t;++i){
		s[i] = 1;
	}
	while(a){
		int k = a%10;
		if(k < t && s[k] == 1){
			s[k] = 0;
		}else{
			return false;
		}
		a /= 10;
	}
	return true;
}

signed main(){
	int l,r,ans = 0;
	cin>>l>>r;
	for(int i = l;i <= r;++i){
		if(f(i)){
		++ans;	
		}
	}
	cout<<ans;
	return 0;
}