#2501 sum_cons_impare

#include <bits/stdc++.h>

using namespace std;

ifstream fin ("unuzero.in");
ofstream fout ("unuzero.out");

long long n;
int main()
{
  cin >> n;
  cout << (n / 2 + 1) * (n / 2 + 1);
  return 0;
}