Arrays

Here are the first examples

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ArrayExamples
{
    class Program
    {
        /* overview of arrays*/

        static void Main(string[] args)
        {
            //manually laying out an array
            //Each element has an index number
            //indexes always start with 0
            int[] myArray = new int[5];
            myArray[0] = 1;
            myArray[1] = 3;
            myArray[2] = 14;
            myArray[3] = 12;
            myArray[4] = 8;

            //you can access an array element by its index
            Console.WriteLine("The third element is {0}", myArray[2]);

            int sum = 0;
            //calculating the sum
            for(int i =0; i<myArray.Length;i++)
            {
                Console.WriteLine(myArray[i]);
                sum += myArray[i]; //sum=sum + myArray[i]
            }

            Console.WriteLine("the sum is {0}", sum);
            Console.WriteLine("The average is {0}", (double)sum / myArray.Length);

            //getting the max
            int max = 0;
            for (int i = 0; i < myArray.Length; i++)
            {
                if (myArray[i] > max)
                {
                    max = myArray[i];
                }
            }

            Console.WriteLine("The maximum value is {0}", max);

            //alternate, easier way. C# contains methods
            //for sum, average, minimum and maximum
            Console.WriteLine(myArray.Sum());
            Console.WriteLine(myArray.Average());
            Console.WriteLine(myArray.Max());
            Console.WriteLine(myArray.Min());

            Console.WriteLine("Press any key to exit");
            Console.ReadKey();
        }
    }
}

the second set of examples

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace arrayExamples2
{
    class Program
    {
        /*more array examples */
        static void Main(string[] args)
        {
            //one way to initialize an array
            //string[] teams = new string[5];
            //another way to initialize an array
            string[] teams = { "Seahawks", "Cardinals", "Rams", "Fourty Niners" };

            //loop through the array and output its content
            for(int i = 0; i < teams.Length; i++)
            {
                Console.WriteLine(teams[i]);
            }

            Console.WriteLine();

            //sort the array elements
            Array.Sort(teams);

            for (int i = 0; i  < teams.Length; i++)
            {
                Console.WriteLine(teams[i]);
            }

            //declare but not iniialize an array
            string[] foods;

            
            Console.WriteLine("how many foods do you want to list?");
            int number = int.Parse(Console.ReadLine());

            //initialize an array in
            foods = new string[number];

            for (int i=0;i <foods.Length;i++)
            {
                //add elements to the array dynamically
                Console.WriteLine("Add a food");
                foods[i] = Console.ReadLine();
            }

            // a different kind of loop: it loops
            //through all the objects in a collection
            //of objects in this case strings
            foreach(string s in foods)
            {
                Console.WriteLine(s);
            }

            //a two dimensional array
            string[,] Books = new string[3, 2];
            Books[0, 0] = "Lord of the rings";
            Books[0, 1] = "J.R.R Tolkein";
            Books[1, 0] = "Ulysses";
            Books[1, 1] = "James Joyce";
            Books[2, 0] = "Gravity's Rainbow";
            Books[2, 1] = "Thomas Pinchon";

            Console.WriteLine("Enter a title");
            string title = Console.ReadLine();

            for (int i = 0; i  < 3; i++)
            {
                if (title.Equals(Books[i, 0]))
                {
                    Console.WriteLine(Books[i, 1]);
                }
               
            }


            Console.WriteLine("Press any key to exit");
            Console.ReadKey();
        }
    }
}

peer excercise

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace peerArray
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] myArray = new int[20];
            Random rand = new Random();

            for(int i = 0;i<20;i++)
            {
                myArray[i] = rand.Next(1, 101);
                Console.WriteLine(myArray[i]);
            }

            Console.WriteLine();
            Console.WriteLine("the Max is {0}", myArray.Max());
            Console.WriteLine("the Min is {0}", myArray.Min());

            Console.WriteLine("Press any key to exit");
            Console.ReadKey();
        }
    }
}