#include <bits/stdc++.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
using mint = atcoder::modint998244353;
using maxt = atcoder::modint1000000007;

int main() {
	int N;
	cin >> N;
	if(N % 2 == 1) {
	  cout << 1 << endl;
	}
	else {
	  cout << N / 2 << endl;
	}
}