<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<cstdio>
using namespace std;
int main(){
int a;
scanf("%d",&a);
printf("%d",2-a*a);
}