<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 n;

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