<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()
{
	int a;
	cin>>a;
	cout<<2-a*a<<endl;
	return 0;
}
