<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);
	return 0;
}