using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        //1. declare an array variable

        // Arrays are often named using a plural noun such as sales

        //double[] sales;

        //New operaator and reserve memory locations 

        //Subscript or index start from 0 to n-1: sales[0], sales[19]

        double[] sales = new double[20];

        int[] myScoresV1 = new int[5] {100, 76, 88, 100, 90};

        int[] myScoresV2 = new int[] {101, 77, 89, 101, 91};

        int[] myScoresV3 = {102, 78, 90, 102, 92};

        char[] arrayOfLetters = new char[] {'h', 'e', 'l', 'l', 'o'};

        string word = new string(arrayOfLetters);

        //Warn: a string is not an array of char 

        //2. Accessing Array Elements

        int[] myScoresExp = {100, 76, 88, 100, 90};

        myScoresExp[0] += 1;

        myScoresExp[1] += 2;

        myScoresExp[2] += 3;

        myScoresExp[3] += 4;

        myScoresExp[4] += 5;

        //can use a loop to perform arithmetic on each element in the array.

        /*

        int sub = 0;

        Console.WriteLine("While loop:");

        while (sub < 5)

        {

            myScoresExp[sub] += 3;

            Console.WriteLine(myScoresExp[sub]);

            ++sub;

        }

        Console.WriteLine("For loop:");

        for (sub = 0; sub <5; sub++)

        {

            myScoresExp[sub] -= 3;

            Console.WriteLine(myScoresExp[sub]);

        }

        */ 

        //Length property

            Console.WriteLine("Array size is {0}", myScoresExp.Length);

            for (int x = 0; x < myScoresExp.Length; x++)

                Console.WriteLine(myScoresExp[x]);

        //Using foreach:  for or while loop that varies a subscript from 0 through Array.Length - 1

        Console.WriteLine("Foreach:");

        double[] payRates = {12.00, 17.35, 21.12, 27.45, 32.22};

        //With the foreach statement, you provide a temporary iteration variable that automatically holds each array value in turn.

        foreach (double money in payRates)

            Console.WriteLine(money.ToString("C"));

        //3. Searching an Array Using a Loop

        int[] validValues = {101, 108, 201, 213, 266, 304, 311, 409, 411, 412};

        double[] prices = {0.89, 1.23, 3.50, 0.69, 5.79, 3.19, 0.99, 0.89, 1.26, 8.00};

        int itemOrdered = 266; //Convert.ToInt32(Console.ReadLine());

        double itemPrice = 0;

        bool isValidItem = false;

        //for Loop

        /*

        for (int x = 0; x < validValues.Length; x++)

        {

            if (itemOrdered == validValues[x])

            {

                isValidItem = true;

                itemPrice = prices[x];

                x = validValues.Length; //break;

            }

        }

        if (isValidItem)

            Console.WriteLine("Price is {0}", itemPrice);

        else

            Console.WriteLine("Sorry - item not found");

        */

        //while loop instead 

        int y = 0;

        while (y < validValues.Length && itemOrdered != validValues[y])

        {

            y++;

        }

        if (y != validValues.Length)

        {

            isValidItem = true;

            itemPrice = prices[y];

        }

        if (isValidItem)

        {

            Console.WriteLine("Item {0} sells for {1}", itemOrdered, itemPrice.ToString("C"));

        }

        else 

            Console.WriteLine("No such item as {0}", itemOrdered);

        //Searching an Array for a Range Match

        int[] discountRangeLowLimits = {1, 13, 50, 100, 200};

        double[] discounts = {0, 0.10, 0.14, 0.18, 0.20};

        int numOfItems = 52;

        double customerDiscount; 

        int sub = discountRangeLowLimits.Length - 1; 

        while (sub >= 0 && numOfItems < discountRangeLowLimits[sub])

            sub--;

        customerDiscount = discounts[sub];

        Console.WriteLine(customerDiscount);

        //Using the BinarySearch() Method

        int[] idNumbers = {122, 167, 204, 219, 345};

        int entryID = 122;

        int z = Array.BinarySearch(idNumbers, entryID); //return -1 if not found, return index if found

        if (z < 0)

            Console.WriteLine("Not found");

        else

            Console.WriteLine("ID {0} found at position {1}", entryID, z);

        //Using the Sort() Method

        string[] names = {"Olive", "Patty", "Richard", "Ned", "Mindy"};

        int q;

        Array.Sort(names);

        for (q = 0; q < names.Length; q++)

            Console.WriteLine(names[q]);

        //BinarySearch() method requires that array elements be sorted in order, the Sort() method is often used in conjunction with it

        Console.WriteLine("---------- Reverse names: ");

        //Using the Reverse() Method

        Array.Reverse(names);

        for (q = 0; q < names.Length; q++)

            Console.WriteLine(names[q]);

        Console.WriteLine("---------- Two-dimensional arrays ");

        //Using Multidimensional Arrays

        //mang 2 chieu 3 dong/row 4 cot/col

        double[,] shippers = new double[3, 4];

        shippers[0,0] = 14D;

        double[,] shippersV2 = {{14.00, 15.00, 16.00, 17.00}, 

                                {21.99, 34.55, 67.88, 31.99},

                                {12.03, 55.55, 32.89, 1.17}};

        int[,] rents = {{400, 450, 510},

                        {500, 560, 630},

                        {625, 676, 740},

                        {1000, 1250, 1600}};

        Console.WriteLine("Enter the floor on which you want to live: ");

        int floor = 2;

        Console.WriteLine("Enter the number of bedrooms you need: ");

        int bedrooms = 1;

        Console.WriteLine("The rent is {0}", rents[floor, bedrooms]);

        //A three-dimensional array definition: rents[building, floor, bedrooms]

        int[,,] builds = {{{400, 500}, {450, 550}, {500, 550}}, //row of value represents of a building (0 to 3)

                      {{510, 610}, {710, 810}, {910, 1010}}, //inner {}represent each floor (0 to 3)

                      {{525, 625}, {725, 825}, {925, 1025}}, //inner inner {} represent bedrooms, (0 -1)

                      {{850, 950}, {1050, 1150}, {1250, 1350}}};

        Console.WriteLine(builds[1, 0, 1]);

        //A jagged array: Two square brackets are used following the data type of the array

        double[][] tickets = {new double[] {5.50, 6.75, 7.95, 9.00, 12.00, 13.00, 14.50, 17.00, 19.00, 20.25},

                              new double[] {5.00, 6.00},

                              new double[] {7.50, 9.00, 9.95, 12.00, 13.00, 14.00},

                              new double[] {3.50, 6.45, 9.95, 10.00, 12.75},

                              new double[] {15.00, 16.00}};

        int route = 1;

        int stop = 0;

        Console.WriteLine("{0} and {1}", tickets[route][stop], tickets[2][3]);

        Console.WriteLine(tickets[route][stop] + tickets[2][3]);

        //Iterating C# 2D Array using Loop

        int[,] series = {{2, 3, 9}, {4, 5, 9}};

        for (int i = 0; i < series.GetLength(0); i++) //numbers.GetLength(0) - gives the number of rows in a 2D array

        {

            Console.Write("row {0} : ", i); 

            for(int j = 0; j < series.GetLength(1); j++) //numbers.GetLength(1) - gives the number of elements in the row

            {

                Console.Write("col{0} ", j);

            }

            Console.WriteLine();

        }

        Console.WriteLine();

        //Iterating through a jagged array

        int[][] jaggedArray = {new int[] {1, 3, 5},

                               new int[] {2, 2}};

        //outer loop: to access the elements (arrays) of the jagged array, jaggedArray.Length - gives the size of jagged array

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

        {

            Console.Write("Element of {0} : ", i);

            //inner loop: to access the elements of the individual array inside the jagged array.

            //jaggedArray[i].Length - gives the size of elements of the ith array inside the jagged array

            for (int j = 0; j < jaggedArray[i].Length; j++)

                Console.Write(jaggedArray[i][j] + ", ");

            Console.WriteLine();

        }

        //Jagged Array with Multidimensional Array

        int[][,] jaggedArrayTwoD = {new int[,] {{1, 8}, {6, 7}},

                                    new int[,] {{0, 3}, {5, 6}, {9, 10}},

                                    new int[,] {{11, 23}, {100, 88}, {0, 10}}

                                   };

        Console.WriteLine(jaggedArrayTwoD[2][0, 1]);

        Console.WriteLine("---------- ");

        //Traversing an array of gender using foreach loop: computes the number of male and female candidates.

        char[] gender = {'m', 'f', 'm', 'm', 'm', 'f', 'f', 'm', 'm', 'm', 'f'};

        int male = 0, female = 0;

        foreach (char g in gender)

        {

            if (g == 'm')

                male++;

            else if (g == 'f')

                female++;

        }

        Console.WriteLine("Male: {0}, Female: {1}", male, female);

        //foreach loop with List (Collection): computes the sum of elements in a List.

        Console.WriteLine(" List (Collection)");

        var numList = new List<int>() {5, -8, 3, 14, 9, 17, 0, 4};

        int sum = 0;

        foreach(int n in numList)

        {

            sum += n;

        }

        Console.WriteLine(sum);

​

    }

}