Олимпиадный тренинг

Задача 27058. Formula - 6


Write a program that calculates the value of y.
\(y = \frac {-1} {x^2}\)


Input
The input is an integer x (x > 0).

Imprint
Print the value y.
 
Examples
# Input Output
1 2 -0.25
2 1 -1