Given is an integer r.
How many times is the area of a circle of radius r larger than the area of a circle of radius 1?
It can be proved that the answer is always an integer under the constraints given.

-----Constraints-----
- $1 \leq r \leq 100$
- All values in input are integers.

-----Input-----
Input is given from Standard Input in the following format:
r

-----Output-----
Print the area of a circle of radius r, divided by the area of a circle of radius 1, as an integer.

-----Sample Input-----
2

-----Sample Output-----
4

The area of a circle of radius 2 is 4 times larger than the area of a circle of radius 1.
Note that output must be an integer - for example, 4.0 will not be accepted.

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