101340: [AtCoder]ABC134 A - Dodecagon

Memory Limit:256 MB Time Limit:2 S
Judge Style:Text Compare Creator:
Submit:0 Solved:0

Description

Score : $100$ points

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

Input

题意翻译

给你一个 $a$,求 $3a^2$ 的值。

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