<image> <image>

*The two images are equivalent, feel free to use either one.

Input

The input contains a single integer a (-100 ≤ a ≤ 100).

Output

Output the result – an integer number.

Example

Input


1


Output


1
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ull unsigned long long
#define vi vector<int>
#define vs vector<string>
#define vl vector<ll>
#define vul vector <ull>
#define pb push_back

int main(void) {
  int n;
  cin >> n;
  cout << 2 - n * n << '\n';
  return 0;
}
