#include <iostream>
#include <string>
#include <vector>
#include <set>
#include <cmath>
#include <algorithm>
#include <iomanip>
using ll = long long;
using namespace std;

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