02. Manipulate Array

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ManipulateArray
{
    class Program
    {
        static void Main(string[] args)
        {
            // Input
            string[] array = Console.ReadLine().Split();
            int commandCount = int.Parse(Console.ReadLine());

            for (int i = 0; i < commandCount; i++)
            {
                // Store command arguments, i.e. "Replace 2 Hello"
                string[] command = Console.ReadLine().Split();
                switch (command[0])
                {
                    case "Reverse":
                        array = ReverseArray(array);
                        break;
                    case "Distinct":
                        array = DistinctArray(array);
                        break;
                    case "Replace":
                        array = ReplaceArrayAt(array, int.Parse(command[1]), command[2]);
                        break;
                    default:
                        break;
                }

            }

            // Output
            Console.WriteLine(string.Join(", ", array));
        }

        /// <summary>
        /// Reverses an array
        /// </summary>
        /// <param name="array"></param>
        /// <returns></returns>
        static string[] ReverseArray(string[] array)
        {
            for (int i = 0; i < array.Length / 2; i++)
            {
                // Index to switch with
                int to = array.Length - 1 - i;

                // Temporary save current value
                string temp = array[i];

                // Switch
                array[i] = array[to];
                array[to] = temp;
            }

            return array;
        }

        /// <summary>
        /// Removes duplicate entiries, leaving only first occurence
        /// </summary>
        /// <param name="array"></param>
        /// <returns></returns>
        static string[] DistinctArray(string[] array)
        {
            // Scan array
            for (int i = 0; i < array.Length; i++)
            {
                for (int j = i + 1; j < array.Length; j++)
                {
                    // If found another occurence -> not unique, remove next occurences
                    if (array[i] == array[j])
                    {
                        array = RemoveValueAt(array, j);
                        j--;
                    }
                }
            }

            return array;
        }

        /// <summary>
        /// Removes given value from a string array
        /// </summary>
        /// <param name="array"></param>
        /// <param name="value"></param>
        /// <returns></returns>
        static string[] RemoveValueAt(string[] array, int atIndex)
        {
            // Shift array left
            for (int i = atIndex; i < array.Length - 1; i++)
            {
                array[i] = array[i + 1];
            }

            // Return shorter array
            string[] newArray = new string[array.Length - 1];
            for (int i = 0; i < newArray.Length; i++)
            {
                newArray[i] = array[i];
            }

            array = newArray;

            return array;
        }

        static string[] ReplaceArrayAt(string[] array, int index, string newValue)
        {
            array[index] = newValue;
            return array;
        }
    }
}