#include <bits/stdc++.h>
using namespace std;
#define int long long
int a, b, ans;
int check(int x) {
	int k = 0, t = x;
	while(t > 0) k++, t /= 10;
	bool flag[15] = {0};
	for(int i = 0;x > 0;i++) flag[x % 10] = 1, x /= 10;
	for(int i = 0;i < k;i++) if(!flag[i]) return 0;
	for(int i = k;i < 10;i++) if(flag[i]) return 0;
	return 1;
}
signed main()  {
	freopen("p1.in", "r", stdin);
	freopen("p1.out", "w", stdout);
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0); 
	cin >> a >> b;
	for(int i = a;i <= b;i++) ans += check(i);
	cout << ans << endl;
	return 0;
}