/*=============================================================

Program name  : Statistical Information

Description   : This program asks for user input and use it as raw data to compute the data set's mean, median, mode, and standarad deviation.

Language      : C#

Members       : Jared Mangeron, Adrian Lenard Mariano

Date Created  : April 9, 2021

Date Modified : April 9, 2021

===============================================================*/

using System;

public class Program

{

    public static void Main()

    { // this program can handle multimodal scenarios

        int dataPoint, data, count = 1, max = 0;

        double mean, median, total = 0, sd, sdNumerator = 0;

        while (true)

        {   // input for the number of data to be collected

            Console.Write("Enter number of data points: ");

            bool correct = Int32.TryParse(Console.ReadLine(), out dataPoint);   // a boolan variable that checks if the input is an integer

            if (correct && dataPoint > 0)

            {

                break;  // if it is an integer greater than zero, the loop breaks and proceeds to the next part of the program

            }

            else

            {   // returns an error if the input is incorrect data type or out of range

                Console.WriteLine("Invalid input! Please enter a whole number greater than 0.\n");

            }

        }

        int[] dataArray = new int[dataPoint];   // array that will hold the raw data input with using the previous input as memory size

        for (int i = 0; i < dataPoint; i++)

        {

            while (true)

            {

                Console.Write("Enter data #{0}: ", i+1);

                bool correct = Int32.TryParse(Console.ReadLine(), out data);    // handles input error

                if (correct)

                {

                    total += data;          // i add each data input to a variable to compute the sum of all the input before putting it inside the array

                    dataArray[i] = data;    // saves the data to the array in a specified index

                    break;

                }

                else

                {   // returns an error if the input is incorrect

                    Console.WriteLine("Invalid input! Please enter a whole number for data input.\n");

                }

            }

        }

        Array.Sort(dataArray);      // sorts the array to ascending order

        mean = total / dataPoint;   // formula for mean

        if (dataPoint%2 == 0)       // computes the median if the total input is even

        {

            double middle = dataArray[dataPoint/2] + dataArray[(dataPoint/2)-1];

            median = middle/2;

        }

        else        // finds the median if the total input is odd

        {

            median = dataArray[(dataPoint-1)/2];

        }

        int[] mode = new int[dataPoint];        // an array that will hold all the mode

        int[] dataCount = new int[dataPoint];   // an array that will hold the counter for each input

        for (int i = 0; i < dataPoint; i++)

        {   // loop for counting how many times a number appeared

            count = 1;

            for (int j = 0; j < dataPoint; j++)

            {

                if (i != j)

                {

                    if (dataArray[i] == dataArray[j])

                    {

                        count += 1;

                    }

                }

            }

            dataCount[i] = count;

        }

        foreach (int i in dataCount)

        {   // this loop will find the maximum value inside the array counter

            if (i > max)

            {

                max = i;

            }

        }

        int index = 0;

        for (int i = 0; i < dataPoint; i++)

        {   // this loop will find all the mode

            if (dataCount[i] == max)

            {

                if (index == 0)

                {   // code for finding the first mode inside the array

                    mode[index] = dataArray[i];

                    index ++;

                }

                else

                {

                    for (int j = 0; j < index; j++)

                    {

                        if (dataArray[i] == mode[j])

                        {

                            break;  // if the same number is already in the array, it is disregarded

                        }

                        if ( j == index -1)

                        {

                            mode[index] = dataArray[i];

                            index++;

                        }

                    }

                }

            }

        }

        index = 0;

        foreach (int i in dataArray)

        {   // computes the standard deviation of the data set

            sdNumerator += (Convert.ToDouble(i) - mean) * (Convert.ToDouble(i) - mean);

        }

        sd = Math.Sqrt(sdNumerator / (dataPoint - 1));

        Console.Write("\n========= Statistical Information =========\nArithmetic mean   : {0}\nMedian            : {1}", mean, median);

        Console.Write("\nMode              : ");

        while (mode[index] != 0)    // since there will be a zero inside the array that holds the mode, i set it as the condition

        {   // prints out all the mode

            Console.Write("{0},", mode[index]);

            index++;

        }

        Console.Write("\b ");

        Console.Write("\nStandard Deviation: {0:0.00000}", sd);

    }

}