<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>
#define ll long long
#define all(x) (x).begin(), (x).end()
#define allr(x) (x).rbegin(), (x).rend()

using namespace std;

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);

    int x;
    cin >> x;
    cout << 2 - x * x;

    return 0;
}