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#include <iostream>


int f(int n)
{
	int sum = 0;
	while (n != 0)
	{
		const int digit = n % 10;
		sum += digit*digit;
		n /= 10;
	}

	return sum;
}

int main()
{
	int k, a, b, sum = 0;
	std::cin >> k >> a >> b;
	if (k < 1 || b < a)
		return -1;

	for (int n = a; n <= b; ++n)
	{
		if (k * f(n) == n)
			++sum;
	}

	std::cout << sum << std::endl;
	return 0;
}