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#include <iostream>
using namespace std;

bool isProperNumber(long long int, long long int);
int square (int);

const int maxNumber = 18 * 81;

int main(int argc, char** argv) {
	long long int k, min, max, newMin, newMax, result, i;
	cin >> k;
	cin >> min;
	cin >> max;
	
	if (min > max) {
		cout << 0;
		return 0;
	}
	
	newMax = (max / k) * k;
	newMin = (min / k) * k == min ? min : (min / k) * k + k;  
	result = 0;
	long long int maximum;
	for (i = newMin; i <= newMax; i += k) {
		if (i / k > maxNumber) {
			cout << result;
			return 0;
		}
		
		if (isProperNumber(i, i / k)) {
			result++;
		}
	}
	cout << result;
	return 0;
}

bool isProperNumber(long long int currentNumber, long long int currentResult) {
	long long int moduloResultSquared;
	while (currentNumber) {
		moduloResultSquared = square(currentNumber % 10);
		currentResult -= moduloResultSquared;
		if (currentResult < 0) {
			return false;
		} else {
			currentNumber /= 10;
		}
	}

	return currentResult == 0 ? true : false;
}

int square(int a) {
	return a * a;
}