#include <iostream>

void sum_of_4_int(int n, int sum, int i, int *count) {
	if (n < sum) {
		return;
	}
	if (sum + (4 - i) * 1000 < n) {
		return;
	}

	if (i < 4) {
		for (int j = 0; j <= 1000; ++j) {
			sum_of_4_int(n, sum + j, i + 1, count);
		}
	} else {
		if (n == sum) {
			(*count)++;
		}
	}
}
int main() {
	int n;
	while (std::cin >> n) {
		int combination;
		sum_of_4_int(n, 0, 0, &combination);
		std::cout << combination << std::endl;
	}
	return 0;
}