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#include <cstdio>
#include <cmath>

int func(int n)
{
	int sum = 0;

	for (int i = n; i >= 1; i = i/10)
		sum += (i % 10)*(i % 10);

	return sum;
}

int main()
{
	int a, b, k;
	int n = 0; // answer, number of ...

	scanf("%d%d%d", &k, &a, &b);

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

	printf("%d\n", n);

	return 0;
}