Problem10725--ABC134 - A - Dodecagon

10725: ABC134 - A - Dodecagon

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

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 $r$.

Input

Input is given from Standard Input in the following format:

```
$r$
```

Output

Print an integer representing the area of the regular dodecagon.

Constraints

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

Sample 1 Input

4

Sample 1 Output

48

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

Sample 2 Input

15

Sample 2 Output

675

Sample 3 Input

80

Sample 3 Output

19200

Source/Category