#include<bits/stdc++.h>
using namespace std;
int main(){
	int a,b,ans = 0;cin>>a>>b;
	for(int i = a;i <= b;++i){
		vector<int> v;
		int tt = i;bool f = 1;
		while(tt!=0)v.push_back(tt%10),tt/=10;
		sort(v.begin(),v.end());
		for(int j = 0;j < v.size();++j)if(j!=v[j])f=0;
		if(f){
			ans++;
		}
	}cout<<ans;
	return 0;
}