using System;

public class Program

{

    public static void Main()

    {

        int[,] arr = new int[7, 7]{

                                {1,2,3,4,5,6,7},

                                {8,9,0,1,2,3,4},

                                {5,6,7,8,9,0,1},

                                {2,3,4,5,6,7,8},

                                {9,0,1,2,3,4,5},

                                {6,7,8,9,0,1,2},

                                {3,4,5,6,7,8,9}

        };

        Rotate90Degree(ref arr);

        DisplayArray(arr);

    }

    /// <summary>

    /// Rotate the array 90 degree inplace

    /// </summary>

    public static void Rotate90Degree(ref int[,] arr)

    {

        //get array columns

        int width = arr.GetLength(0);

        for (int i = 0; i < width /2 ; i++)

        {

            for (int j = i; j < width-i-1; j++)

            {

                //store value of top 

                int temp=arr[i,j];

                //move left to top

                arr[i,j]=arr[width-1-j,i];

                //move bottom to left

                arr[width-1-j,i]=arr[width-1-i,width-j-1];

                //move right to bottom

                arr[width-1-i,width-j-1]=arr[j,width-i-1];

                //assign temp to right 

                arr[j,width-i-1]=temp;

            }

        }

    }

    public static void  DisplayArray(int[,] arr)

    {

        int width = arr.GetLength(0);

​

        string result = "";

        for (int i = 0; i < width; i++)

        {

            for (int j = 0; j < width; j++)

            {

                result+=arr[i, j] + " ";

            }

            result += "\n";

        }

        Console.WriteLine(result);

    }

}