#include<bits/stdc++.h>
using namespace std;
#define int long long

inline int read(){
	int x = 0,f = 1;char c = getchar();
	while(!isdigit(c)){if(c == '-')f = -1;c = getchar();}
	while(isdigit(c)){x = x*10 + c-'0';c = getchar();}
	return x*f;
}

int t[10];

bool check(int k){
	for(int i = 0;i <= 9;i++)t[i] = 0;
	string s = to_string(k);
	for(int i = 0;i < s.size();i++)t[s[i]-'0']++;
	for(int i = 0;i <= 9;i++){
		if(i < s.size() && t[i] != 1)return 0;
		if(i >= s.size() && t[i])return 0;
	}
	return 1;
}

signed main(){
	int a = read(),b = read(),sum = 0;
	for(int i = a;i <= b;i++)
		sum += check(i); 
	cout << sum;
	return 0;
}