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