#include<bits/stdc++.h>
using namespace std;
bool f(int n){
	bool b[20]{}; 
	while(n!=0){
		int g=n%10;
		n/=10;
		if(b[g]==1) return 0;
		b[g]=1;
	}
	int x=0;
	while(b[x]==1){
		x++;
	}
	while(x<=9){
		if(b[x]==1) return 0;
		x++;
	}
	return 1;
}
int main(){     
	int a,b,s=0;
	cin>>a>>b;
	for(int i=a;i<=b;i++){
		if(f(i)==1) s++;
	}
	cout<<s;
	return 0;   
}