// Programmer: June Oh

// Program Name: Simple Statistics 

// Date: 12/8/2024-12/10/2024

// Description: This program generates a random array of 100 numbers from -50 to 50 and displays the result

using System;

using System.Collections.Generic;//to use List<int>

​

public class Program

{

    public static void Main()

    {

        loop1:

        Console.WriteLine("Welcome to the Number Generator: ");

        Console.WriteLine("{0}{1}","Random Numbers: ","\n");

        Random rg= new Random();//make a random fuction

        int randomno=0;//assign integer variables

        int evenno=0;

        List<int> numbers = new List<int>();//make a list for random numbers

        List<int> evennumbers = new List<int>();//make a list for even numbers

        List<int> primenumbers = new List<int>();//make a list for prime numbers

        for (int i=0; i<5; i++)//five columns

        {

            for (int j=0; j<20; j++)//20 rows

            {

                randomno=rg.Next(-50,51);//random numbers from -50 to 50

                if (i==4&&j==19)// if it is the last number on the list

                    Console.Write("{0,3}",randomno);//no comma after

                else// if it is not

                Console.Write("{0,3}{1}",randomno,", ");//display comma after numbers

                numbers.Add(randomno);//add random numbers to the numbers list

                if (randomno%2==0)//if it is even,

                {

                    evenno=randomno;

                    evennumbers.Add(evenno);//add even numbers in the evennumbers list

                }

            }

            Console.WriteLine("\n");

        }

        Console.WriteLine("{0}{1}","Even Numbers: ","\n");//display the result with the alignment

        int c=0;

        foreach (int i in evennumbers)//go through all elements in the list

        {

            c++;

            Console.Write("{0,3}",i);//print all elements in the list

            if (c<evennumbers.Count)//if c is smaller than its length

                Console.Write(", ");//print comma

            if (c%20==0)//if 20 even numbers are printed,

                Console.WriteLine("\n");//go to a new line

        }

        c=0;

        Console.WriteLine("\n"+new string('-',99));//separate the section

        int sum=0;//int sum, max, min=0

        int max=0;

        int min=0;

        foreach (int i in numbers)//go through every element in numbers list

        {

            sum+=i;//sum of every element is sum

            if (i>max) max=i;//max is the largest number in the list

            if (i<min) min=i;//min is the smallest number in the list

            if (function(i))//apply the function and if it is true,

            {

                primenumbers.Add(i);//add that number to the primenumbers list

            }

        }

        Console.WriteLine("{0}{1}","Sum of all random numbers:", sum);//display the result

        Console.WriteLine("{0}{1}","Maximum value:", max);

        Console.WriteLine("{0}{1}","Minimum value:", min);

        Console.WriteLine("{0}{1:N2}","Average of all random numbers:", (double)sum/numbers.Count);

        Console.Write("All prime numbers are: ");

        primenumbers.Sort();//from the smallest to the largest

        foreach (int i in primenumbers)//go through all elements in the primenumbers list

        {

            c++;

            Console.Write("{0}",i);//print all elements in the list

            if (c<primenumbers.Count)//if c is smaller than its length

                Console.Write(", ");//add comma

        }

        Console.WriteLine();

        if(replay()==true)//for the replay

        {

            Console.Clear();//clear the screen

            goto loop1;//goto loop1;

        }

    }

    static bool function(int p)//create a function to determine prime that returns true or false

    {

        if (p <= 1) return false;//p cannot be negative

        if (p==2||p==3) return true;//2 or 3 are prime

        for (int i=2; i*i<=p; i++)//for a number of 4 or larger

        {

            if (p%i==0) return false;//if p is divided by i, p is not a prime           

        }

        return true;//else would be true

    }

    public static bool replay()//replay function which retunrs ture or false

    {

        while(true)//repeat until the value evaliated to false

        {

            Console.WriteLine("would you like to try again?");//ask users for the replay and store the answer

            string ans2=Console.ReadLine();

            if (ans2.Substring(0,1).ToUpper() == "Y")//if they like to replay,

                return true;

            else if(ans2.Substring(0,1).ToUpper() == "N")//if they do not,

            {

                Console.WriteLine("byebye :)");//byebye

                break;//exit the loop

            }

            Console.WriteLine("Please enter a valid answer");

        }

        return false;//return the value

    }

}