Problem Statement

It is known that the area of a regular dodecagon inscribed in a circle of radius $a$ is $3a^2$.

Given an integer $r$, find the area of a regular dodecagon inscribed in a circle of radius $r$.

Constraints

• $1 \\leq r \\leq 100$
• $r$ is an integer.

Input

Input is given from Standard Input in the following format:

$r$

Output

Print an integer representing the area of the regular dodecagon.

Sample Input 1

4

Sample Output 1

48

The area of the regular dodecagon is $3 \\times 4^2 = 48$.

Sample Input 2

15

Sample Output 2

675

Sample Input 3

80

Sample Output 3

19200