/*

The following program generates an array of random numbers between 1 and 200.

It then proceeds to identify the current highest number in the array which it prints to screen 

before redicing the elemen't value to 0 to allow it to find the next highest.

*/

​

using System;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

​

        int inputNum = 0;

​

        Console.WriteLine("Input a number that you want to check for prime number");

​

        while (!int.TryParse(Console.ReadLine(), out inputNum))

        {

            Console.WriteLine("invalid input, try again!");

        }

​

        List<int> primeList = primeGenerator(inputNum);

​

        bool isPrime = true;

        int currentCheckNum = 2;

        while (isPrime && currentCheckNum<inputNum/2+1)

        {

            if (inputNum % currentCheckNum == 0)

            {

                Console.WriteLine("The number " + inputNum + " is not a prime number.");

                isPrime = false;

            }

            else

            {

                currentCheckNum++;

            }

        }

​

        if (isPrime)

            Console.WriteLine("The number " + inputNum + " is a prime number.");

​

        if (primeList.Contains(inputNum))

            Console.WriteLine("found the number from prime list");

​

    }

​

    public static List<int> primeGenerator(int maxValue)

    {

        List<int> result = new List<int>();

​

        result.Add(2);

​

        Console.WriteLine("Generating the numbers. Your computer is slow.");

​

        DateTime beginTime = DateTime.Now;

​

        for (int i = 3; i <= maxValue; i++)

        {

​

            bool isPrime = true;

​

      foreach (var item in result)

      {

                if(i%item==0)

        {

                    isPrime = false;

                    break;

        }

      }

​

​

            if (isPrime)

            {

                result.Add(i);

                Console.Write(result[result.Count - 1] + " ");

            }

​

        }

​

        TimeSpan duration = DateTime.Now - beginTime;

​

        Console.WriteLine("Generating Done. Duration: " + duration) ;

​

        return result;

    }

​

​

}