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#include <cstdio>

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

int main() {
	long long k, a, b;
	scanf("%lld%lld%lld", &k, &a, &b);

	long long result = 0;
	for (long long i = a + k - a % k; i <= b; i += k) {
		if (i / k == f(i))
			result++;
	}

	printf("%lld\n", result);
	return 0;
}