Array exercise #4

            /* 
 In your code declare a variable to hold a six-digit ticket number. Ticket numbers are
 designed so that if you drop the last digit of the number, then divide the number by 7,
 the remainder of the division will be identical to the last dropped digit. This process
 is illustrated in the following example:
 a. Assign a value for the ticket number; for example, 123454.
 b. Remove the last digit, leaving 12345.
 c. Determine the remainder when the ticket number is divided by 7. In this case,
 12345 divided by 7 leaves a remainder of 4.
 d. Assign the Boolean value of the comparison between the remainder and the digit
 dropped from the ticket number. To compare two values, use the == symbol (double
 equals).
 e. Display the result - true or false –
 Test the application with the following ticket numbers:
 • 123454; the comparison should evaluate to true
 • 147103; the comparison should evaluate to true
 • 154123; the comparison should evaluate to false */


            int[] tickets = { 123454, 147103, 154123 };
            foreach (int ticket in tickets)
            {
                Console.WriteLine($"{ticket} : {((ticket / 10) % 7 ) == (ticket % 10)}");
            }

            //or 

            int ticket = 123454;
            Console.WriteLine($"{ticket} : {((ticket / 10) % 7) == (ticket % 10)}");

            int ticket1 = 147103;
            Console.WriteLine($"{ticket1} : {((ticket1 / 10) % 7) == (ticket1 % 10)}");

            int ticket2 = 154123;
            Console.WriteLine($"{ticket2} : {((ticket2 / 10) % 7) == (ticket2 % 10)}");

            //or 
            int ticket2 = 154123;
            int first5digit = ticket2 / 10; // first five digit which is 15412, leftover is 3 
            int lastdigit = ticket2 % 10; // 154123/10 leftover is 3 
            int remainder = ticket2 % 7; // leftover is 4 
            bool isValid = remainder == lastdigit;
            Console.WriteLine(isValid);

 Console.WriteLine("Task One");
            //Write code for an array that can hold 10 integers.Fill the array with 10 random
            //integer numbers between 0 and 70.
            //Display the integers from first to last, and then display the integers from last to
            //first.

            int[] numbers = new int[10];

            var random = new Random();
            Console.WriteLine("Printing the numbers from index 0 to 9");
            for(int i = 0; i < numbers.Length; i++)
            {
                numbers[i] = random.Next(0, 71);
                Console.WriteLine(numbers[i]);
            }

            Console.WriteLine("Printing the numbers from index 9 to 0");
            for (int i = numbers.Length -1; i > -1; i--)
            {
                Console.WriteLine(numbers[i]);
            }

//Write code that prompts the user to make a choice for a pizza size - S, M, L, or X - and then displays the price as 
            //$6.99, $8.99, $12.50, or $15.00, accordingly.
            //Display an error message if the user enters an invalid pizza size. 
            //(Note: to read a char from the user use the following: ReadKey().KeyChar from the Console class).

            char[] sizes = { 'S', 'M', 'L', 'X' };
            double[] prices = { 6.99, 8.99, 12.50, 15, 00 };

            Console.Write("Enter the size of the pizza: ");
            char size = Console.ReadKey().KeyChar;
            bool valid = false; 

            for(int i = 0; i < sizes.Length; i++)
            {
                if (sizes[i] == size)
                {
                    Console.WriteLine($"\nThe price is: {prices[i]}");
                    valid = true; 
                }    
            }

            if (!valid)
            {
                Console.WriteLine("\nInvalid pizza size!!");
            }

            //Write code that reads an unspecified number of scores and determines how many scores are above or equal 
            //to the average and how many scores are below the average.
            //Enter a negative number to signify the end of the input.Assume that the maximum number of scores is 100.

            int[] scores = new int[10];
            int count = 0, total = 0; 

            for(int i = 0; i < scores.Length; i++)
            {
                Console.Write($"Enter the score: ");
                int score = int.Parse(Console.ReadLine()); 
                if (score < 0)
                {
                    break;
                }
                scores[i] = score;
                total += score; 
                count++;
            }

            double average = total / count;
            int aboveOrEqualToAverage = 0, belowAverage = 0; 
            for(int i = 0; i < count; i++)
            {
                if(scores[i] >= average)
                {
                    aboveOrEqualToAverage++; 
                }
                else
                {
                    belowAverage++; 
                }
            }
            Console.WriteLine($"Average : {average}");
            Console.WriteLine($"Scores above or equal to the average {aboveOrEqualToAverage}");
            Console.WriteLine($"Scores below the average: {belowAverage}");

Console.WriteLine("Task Four");
            //Write code that asks the user for 7 integer numbers and display the even ones.
            //Call your class TaskFour.cs and your method FindEvenNumbers
            //Here is a sample run:

            int[] numbers = new int[10];
            int EvenNumberCount = 0; 
            for (int i = 0; i < numbers.Length; i++)
            {
                Console.Write($"Enter number: ");
                numbers[i] = int.Parse(Console.ReadLine());
                if (numbers[i] % 2 == 0)
                {
                    EvenNumberCount++;
                }
            }

            Console.Write("\nEven numbers: ");
            for (int i = 0; i < numbers.Length; i++)
            {
                if (numbers[i] % 2 == 0)
                {
                    Console.Write($"{numbers[i]}   ");
                }
            }

//Write a program that generates 20 random integers between 0 and 9 and displays the count for each number.
            //Use an array of ten integers, say counts, to store the counts for the number of 0s, 1s, ..., 9s.)

            var random = new Random();
            int[] numbers = new int[20];
            int[] counts = new int[10];

            Console.WriteLine("Numbers Generated: ");

            for (int i = 0; i < numbers.Length; i++)
            {
                numbers[i] = random.Next(0, 9);
                Console.WriteLine($"{numbers[i]}");
                counts[numbers[i]]++; 
            }

            for (int i = 0; i < counts.Length; i++)
            {
                Console.WriteLine($"Number of {i}'s: {counts[i]}");
            }