#include <bits/stdc++.h>
#define rep(i, a) for (int i = 0; i < (a); i++)
#define rep2(i, a, b) for (int i = (a); i < (b); i++)
#define repr(i, a) for (int i = (a) - 1; i >= 0; i--)
#define repr2(i, a, b) for (int i = (b) - 1; i >= (a); i--)
using namespace std;
typedef long long ll;

int main() {
	int n;
	cin >> n;
	if (n % 2 == 0) {
		cout << n / 2 << endl;
	} else {
		cout << n << endl;
	}
	return 0;
}