<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
import collections
# from sys import stdout, stdin # if I will need to print(elements like C++ do)
# input = stdin.readline
# print = stdout.write
def main():
    print(2 - int(input()) ** 2)

if __name__ == '__main__':
    main()