using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

​

/*

    Grant Matherne

    Student Grade Tracker

*/

​

namespace StudentGradeTracker

{

    internal class Program

    {

        static void Main(string[] args)

        {

            bool run = true;

            int[,] grades = null;

​

            while (run)

            {

                int mode;

                do

                {

                    Console.WriteLine($"\nMain Menu\n=====================\n1) Initialize Student Data\n2) Input Grades\n3) Calculate Subject Statistics\n4) Display Grades\n5) Exit\n");

                } while (!int.TryParse(Console.ReadLine(), out mode) || mode < 1 || mode > 5);

                Console.WriteLine("===================\n");

​

​

                switch (mode)

                {

                    case 1:

​

                        int rows;

                        do

                        {

                            Console.Write("Enter number of students: ");

                        } while (!int.TryParse(Console.ReadLine(), out rows) || rows < 1);

​

                        Console.WriteLine();

​

                        int cols;

                        do

                        {

                            Console.Write("Enter number of subjects: ");

                        } while (!int.TryParse(Console.ReadLine(), out cols) || cols < 1);

​

                        Console.WriteLine();

​

                        grades = new int[rows, cols];

​

                        break;

                    case 2:

​

                        if(grades == null)

                        {

                            Console.WriteLine("Intitialize student data first");

                            break;

                        }

​

                        for (int i = 0; i < grades.GetLength(0); i++)

                        {

                            for (int j = 0; j < grades.GetLength(1); j++)

                            {

                                int grade;

                                do

                                {

                                    Console.Write($"Enter student {i + 1} subject {j + 1} grade: ");

                                } while (!int.TryParse(Console.ReadLine(), out grade) || grade < 0 || grade > 100);

                                grades[i, j] = grade;

                            }

                        }

​

                        break;

                    case 3:

​

                        if (grades == null)

                        {

                            Console.WriteLine("Intitialize student data first");

                            break;

                        }

​

                        Console.WriteLine();

                        for (int i = 1; i <= grades.GetLength(1); i++)

                        {

                            Console.WriteLine($"=============\nSubject {i}");

                            printSubjectStuff(grades, i - 1);

                        }

​

                        Console.WriteLine("===============\n");

​

                        break;

                    case 4:

​

                        if (grades == null)

                        {

                            Console.WriteLine("Intitialize student data first");

                            break;

                        }

​

                        Console.Write("\n                ");

                        for (int i = 0; i < grades.GetLength(1); i++)

                        {

                            Console.Write($"Subject {i + 1}   ");

                        }

                        Console.WriteLine();

​

                        for (int i = 0; i < grades.GetLength(0); i++)

                        {

                            Console.Write($"Student {i + 1}");

                            for (int j = 0; j < grades.GetLength(1); j++)

                            {

                                Console.Write($"{grades[i, j],12:F0}");

                            }

                            Console.WriteLine();

                        }

​

                        break;

                    case 5:

                        run = false;

                        break;

                }

            }

        }

​

        public static void printSubjectStuff(int[,] grades, int col)

        {

            Console.WriteLine($"\nMin: {getSubjectExtreme(grades, true, col)}\nMax: {getSubjectExtreme(grades, false, col)}\nAverage: {getSubjectAverage(grades, col),0:F2}");

        }

​

        public static double getSubjectAverage(int[,] array, int col)

        {

            double sum = 0;

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

            {

                 sum += array[i, col];

            }

            return sum / array.GetLength(0);

        }

​

        public static int getSubjectExtreme(int[,] array, bool min, int col)

        {

            int direction = (min? 1:-1);

​

            int extreme = array[0,col];

​

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

            {

                if (array[i,col] * direction < extreme * direction)

                {

                    extreme = array[i,col];

                }

            }

            return extreme;

        }

​

    }

}