Problem:
Score : 100 points

Problem Statement

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 1

2

Sample Output 1

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.

Sample Input 2

100

Sample Output 2

10000

Solution in C# (Mono 4.6.2.0) (judge verdict: Runtime Error)

using System;
using System.Diagnostics;

namespace atcode
{
    class Program
    {

        static void Main(string[] args)
        {
            
            int inputN = int.Parse(Console.ReadLine());

            string inputS = Console.ReadLine().Trim();

            if(inputN%2 == 1)
            {
                Console.WriteLine("No");
                //Debug.WriteLine("No");
                return;
            }

            int tLen = inputN / 2;
            string t1 = inputS.Substring(0, tLen);
            string t2 = inputS.Substring(tLen, tLen);
            //Debug.WriteLine($"t1:{t1}");
            //Debug.WriteLine($"t2:{t2}");
            if (t1.Equals(t2))
            {
                Console.WriteLine("Yes");
                //Debug.WriteLine("Yes");
                return;
            }
            else
            {
                Console.WriteLine("No");
                //Debug.WriteLine("No");
                return;
            }
        }
    }
}