<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 <iostream>
using namespace std;

int main() {
	// your code goes here
	    long long p;
	    cin>>p;
	    cout<<2-p*p<<endl;
	return 0;
}
