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#include <iostream>

using namespace std;

const int maxFn = 1458; // 18 * 81;
const unsigned long long limit = 1000000000000000000L; // 10 ^ 18
const unsigned long long maxK = limit / maxFn; // avoid exceeding long limit

int squares[10];

unsigned int f(unsigned long long n) {
	unsigned long long reminder = n;
	unsigned int sum = 0;
	while (reminder > 0) {
		sum += squares[(int) (reminder % 10)];
		reminder = reminder / 10;
	}
	return sum;
}

int main() {

	for (int i = 0; i < 10; i++) {
		squares[i] = i * i;
	}

	ios::sync_with_stdio(false);
	unsigned long long k, a, b, result = 0;
	cin >> k;
	cin >> a;
	cin >> b;

	// Optimize input values
	if (k > a) a = k;
	if (k < b / maxFn) { // equivalent of: if (k * maxFn < b) b = k * maxFn;
		b = (k >= maxK) ? limit : (k * maxFn);
	}

	// n must be divisible with no rest by k
	unsigned long long start = (a % k == 0) ? a : (a + k - (a % k));
	unsigned long long end = (b % k == 0) ? b : (b - (b % k));

	// Find matching n
	for (unsigned long long n = start; n <= end; n += k) {
		if (k * f(n) == n) {
			result += 1;
		}
	}
	cout << result << endl;

	return 0;
}