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#include <iostream>
#include <algorithm>
using namespace std;

typedef long long ll;

const ll FN_MAX = 20*9*9;

ll k, a, b;

ll do_fn(ll n) {
	ll res = 0;
	while (n) {
		ll d = n % 10;
		res += d*d;
		n /= 10;
	}
	return res;
}

int main() {
	cin >> k >> a >> b;
	
	int ans = 0;
	for (ll fn = min(b / k, FN_MAX); fn * k >= a; fn--) {
		if (fn * k > b) continue;
		
		ll n = fn * k;
		if (do_fn(n) == fn) ans++;
		
		// cout << "fn=" << fn << endl;
	}
	
	cout  << ans << '\n';
	return 0;
}