#include <bits/stdc++.h>
typedef  long long ll;
#define INF 1000000000
using namespace std;
#define MOD 1000000007

int main(void){
    int n;
    cin>>n;
    int ans;
    if(n%2==0){
        ans=n/2;
    }else{
        ans=n;

    }
    cout<<ans<<endl;
}