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

int a, b, ans = 0, c[10];

int ws(int n)
{
	int ans1 = 0;
	while (n)
	{
		n /= 10;
		ans1++;
	}
	return ans1;
}

int aa(int x, int y)
{
	memset(c, 0, sizeof(c));
	while (y)
	{
		int ax = y % 10;
		c[ax]++;
		y /= 10;
	}
	for (int i = 0; i < x; i++)
	{
		if (c[i] != 1) return 0;
	}
	return 1;
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0), cout.tie(0);
	cin >> a >> b;
	for (int i = a; i <= b; i++)
	{
		int p = ws(i);
		ans += aa(p, i);
	}
	cout << ans;
	return 0;
}