Answer to Question #332535 in C# for Siyanda

Question

Write a user defined method named getMark that can be used to get a valid mark from the user.

Your method must continuously ask the user for a mark, until a valid mark is entered (valid marks

are between 0 and 100). If a user enters an invalid mark, display an error message before asking

for a valid mark to be entered. The method must return the valid value to the calling program.

Write a user defined method named isPass that can be used to determine whether a mark is a

pass mark (greater or equal to 50). The method must take as input a mark, and return a boolean,

indicating whether the mark was a pass mark.

Write a program that reads in 5 marks by using the getMark method to ensure that valid marks are

processed. You need to calculate the sum and the average of the marks. Your program must also

use the isPass method to determine the number of pass marks entered. When the 5 marks have

been processed you need to display the sum, average and number of passes (from these marks).

Answer 1

using System;
using System.Linq;
using System.Text;


class Program
{
    static void Main()
    {
        int[] marks = new int[5];
        Console.WriteLine("Input 5 marks.");
        for (int i = 0; i < marks.Length; i++)
        {
            Console.Write($"{i + 1}.");
            marks[i] = GetMark();
        }


        Console.WriteLine($"Marks: {string.Join(" ", marks)}");
        Console.WriteLine($"Sum: {marks.Sum()}");
        Console.WriteLine($"Avg: {marks.Average()}");
        Console.WriteLine($"Number of passes marks: {marks.Count(x => IsPass(x))}");
    }


    static int GetMark()
    {
        while (true)
        {
            Console.Write("Enter a mark (0-100): ");
            if (int.TryParse(Console.ReadLine(), out int output) && output >= 0 && output <= 100)
                return output;


            Console.WriteLine("Incorrect input! Please, try again.");
        }
    }


    static bool IsPass(int mark)
    {
        return mark >= 50;
    }
}