The square and triangle
Very easy
Execution time limit is 1 second
Runtime memory usage limit is 64 megabytes
Given a square with side a, in which an isosceles triangle is inscribed. Determine the area of this triangle.
Input
One real number a (1 ≤ a ≤ 10^18).
Output
Print one number - the area of the triangle.
Examples
Input #1
Answer #1
Input #2
Answer #2
Submissions 1K
Acceptance rate 56%