<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 <stdio.h>
 
int main() {
	int x;
 
	scanf("%d", &x);
	printf("%d\n", 2 - x * x);
	return 0;
}