using System;

​

public class Program

{ 

    public static void Shuffle (int [] arr)

{ 

    Random rnd = new Random ();

    int count=0;

    int num1, num2;

    while (count<30)

    { 

        num1=rnd.Next(arr.Length);

        num2=rnd.Next(arr.Length);

        if (num1!=num2)

        { 

            int temp=arr[num1];

            arr[num1]=arr[num2];

            arr[num2]=temp;

        }

    }

}

    public static void Main()

    {

    }

}