using System;

​

​

​

public abstract class Shapes{

​

public abstract int square(int side);

}

​

public class Square : Shapes

{

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public override int square(int side){

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return side * side;

}

​

    public static void Main()

    {

    Square obj =new Square();

        Console.WriteLine("Enter Value to find square.");

        var val = Console.ReadLine();

        Console.WriteLine(obj.square(int.Parse(val)));

    }

}