using System;

public class Program

{

    public static void Main()

    {

/ Step 1: create array.

int[] array1 = { 1, -1, -2, 0 };

​

// Step 2: use simple Max to find maximum number.

Console.WriteLine(array1.Max());

​

// Step 3: find maximum number when all numbers are made positive.

Console.WriteLine(array1.Max(element => Math.Abs(element)));

    }

}