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#include <iostream>
#include <vector>

long long f(long long n)
{
	long long s = 0;
	while (n != 0)
	{
		s += (n%10LL)*(n%10LL);
		n /= 10;
	}
	return s;
}

long long numOfDigits(long long n)
{
	long long s = 0;
	while (n != 0)
	{
		s += 1;
		n /= 10;
	}
	return (s == 0 ? 1 : s);
}

int main(void)
{

	long long k, a, b, x, n, maxX;
	std::vector<long long> solutions;

	std::cin >> k >> a >> b;

	x = ( a % k > 0 ? a / k + 1 : a / k );
	n = x * k;

	maxX = numOfDigits(b) * 9*9;

	for(; x <= b/k; x++, n += k)
	{
		if( f(n) == x ) 
		{
			solutions.push_back(n);
		}

		if ( x > maxX ) break;
	}

	std::cout << solutions.size();

	return 0;
}