/*

Example 1:

​

Input: rating = [2,5,3,4,1]

​

Output: 3

​

Explanation: We can form three teams given the conditions. (2,3,4), (5,4,1), (5,3,1).

​

ideas: 

1. all subsequece with length = 3, desc / asc

2. to find subsequence: recursion / iteration. iteration for the problem 

3. three nested loops to find all subsequence and record those can satisfy the requirments .

4. time complexisty: O(n^3)

​

*/

​

/*

image[x][y] n * n

​

input 

1: x = 0 y = 0 ---> x = 0, y = 2

2: x = 0 y = 1 ---> x = 1, y = 2

3: x = 0 y = 2 ---> x = 2, y = 2     function: new x ---> old y; new y ---> n - 1 - old x

4: x = 1 y = 0 ---> x = 0, y = 1

5: x = 1 y = 1 ---> x = 1, y = 1

6: x = 1 y = 2 ---> x = 2, y = 1

7: x = 2 y = 0 ---> x = 0, y = 0

8: x = 2 y = 1 ---> x = 1, y = 0

9: x = 2 y = 2 ---> x = 2, y = 0

​

1 2 --->   3 1

3 4        4 2

1: x = 0 y = 0 ---> x = 0, y = 1

2: x = 0 y = 1 ---> x = 1, y = 1

3: x = 1 y = 1 ---> x = 0, y = 0     function: new x ---> old y; new y ---> n - 1 - old x

4: x = 1 y = 0 ---> x = 1, y = 0

​

​

​

​

this does not work 

swap the value of (image[x][y], image[y][x]}

​

 1 2 3

 4 5 6

 7 8 9

 1 4 7

 2 5 8

 3 6 9

​

​

*/

​

​

​

using System;

public class Program

{

    public static int FindSubsequence(int[] array)

    {

        int count = 0;

        for (int i = 0; i < array.Length; i++)

        {

            int[] sub = new int[3];

            sub[0] = array[i];

            for (int j = i + 1; j < array.Length; j++) 

            {

                sub[1] = array[j];

                for (int k = j + 1; k < array.Length; k++)

                {

                    sub[2] = array[k];

                    if (sub[0] < sub[1] && sub[1] < sub[2] || sub[0] > sub[1] && sub[1] > sub[2]) 

                    {

                        count++;

                    }

                }

            }

        }

        return count;

    }

    public static void rotateImage(int[][] image)

    {

        int n = image.Length;

        int temp = 0;

        int mid = n / 2;

        // reverse top and bottom

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

        {

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

            {

                temp = image[i][j];

                image[i][j] = image[n - 1 - i][j];

                image[n - 1 - i][j] = temp;

            }

        }

​

        // transpose

​

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

        {

            for (int j = i; j < n; j++)

            {

                temp = image[i][j];

                image[i][j] = image[j][i];

                image[j][i] = temp;

            }

        }   

​

    }

​

    public static void Main()

    {

        //Console.WriteLine("Hello World");

        //int[] array = {2, 5, 3, 4, 1};

        //int[] array = {1, 2, 3, 4};

        int[] array = {2, 1, 3};

        int res = Program.FindSubsequence(array);

        Console.WriteLine(res);

        int n = 3;

        int[][] image = new int[n][];

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

        {

            image[i] = new int[n];

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

            {

                image[i][j] = i * n + j + 1;

            }

        }

        Console.WriteLine("Printing Image: ");

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

        {

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

            {

                Console.Write(image[i][j] + "\t");

            }

            Console.WriteLine();

        }

        rotateImage(image);

​

        Console.WriteLine("Printing Rotated Image: ");

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

        {

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

            {

                Console.Write(image[i][j] + "\t");

            }

            Console.WriteLine();

        }       

​

    }

}