1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
#include <iostream>
using namespace std;

int sum_of_squares(long long k) {
	int result = 0;
	while (k) {
		result += (k % 10) * (k % 10);
		k /= 10;
	}
	return result;
}

int main()
{
	ios_base::sync_with_stdio(0);
	long long a, b, c, result = 0;
	cin >> c >> a >> b;
	for (long long i = 1; i < 1500; i++) {
		if (i * c < a) {
			continue;
		}
		if (i * c > b) {
			break;
		}
		int sum = sum_of_squares(i * c);
		if (sum == i) {
			result++;
		}
	}
	cout << result << endl;
    return 0;
}