<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;

int main()
{
    //freopen("in", "r", stdin);
    //freopen("out", "w", stdout);

    int a;
    scanf("%d", &a);
    printf("%d\n", 2 - a * a);
    return 0;
}