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/*
 *  Copyright (C) 2015  Paweł Widera
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details:
 *  http://www.gnu.org/licenses/gpl.html
 */
#include <iostream>
using namespace std;	

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	unsigned long long int k, a, b;
	cin >> k >> a >> b;

	auto start = (a / k + 1) * k;
	if (a % k == 0) {
		start = a;
	}

	int count = 0;
	for (auto i = start; i <= b; i += k) {
		auto value = i / k;
		auto digits = to_string(i);

		// stop if not enough digits to match the value
		if (9 * 9 * digits.size() < value) {
			break;
		}

		for (auto digit : digits) {
			value -= (digit - 48) * (digit - 48);
		}
		if (value == 0) {
			count += 1;
		}
	}

	cout << count << endl;
	return 0;
}