#include <bits/stdc++.h>
using namespace std;
int main () {
	int n;
	cin >> n;
	long long z = 1, m = 1;
	for (int i = 1; i < n; i++) {
		if (m == 1) {
			m = z + 1;
			z = 1;
		} else {
			m -= 1;
			z += 1;
		}
	} 
	cout << z << "/" << m;
	return 0;
}