#include<iostream>
#include<string>
using namespace std;
string s;
int a,b,ans;
bool f;
void check(int x,int step){
	int t=x;
	for(int i=0;i<step;i++){
		t=x;
		f=false;
		while(t!=0){
			
			if(t%10==i){
				//cout<<t%10<<" "<<i<<" ";
				f=true;
				break;
			}			
			t/=10;
			//cout<<endl;
		}
		if(f==false){
			//cout<<1<<endl<<endl;
			return;	
		} 
	}
}
int main(){
	cin>>a>>b;
	for(int i=a;i<=b;i++){
		s=to_string(i);
		check(i,s.length());
		if(f){
			//cout<<i<<endl;
			ans++;
		}
	}
	cout<<ans<<endl;
	return 0;
}