Array Modifier

using System;
using System.Linq;

namespace _02._Array_Modifier
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] arr = Console.ReadLine()
                .Split(' ', StringSplitOptions.RemoveEmptyEntries)
                .Select(int.Parse)
                .ToArray();

            string command = Console.ReadLine();

            while (command != "end")
            {

                string[] cmd = command.Split(' ', StringSplitOptions.RemoveEmptyEntries).ToArray();
                string action = cmd[0];

                if (action == "swap")
                {
                    int index1 = int.Parse(cmd[1]);
                    int index2 = int.Parse(cmd[2]);

                    int temp = arr[index1];
                    arr[index1] = arr[index2];
                    arr[index2] = temp;

                }
                if (action == "multiply")
                {
                    int index1 = int.Parse(cmd[1]);
                    int index2 = int.Parse(cmd[2]);
                    arr[index1] = arr[index1] * arr[index2];
                }
                if (action == "decrease")
                {
                    for (int i = 0; i < arr.Length; i++)
                    {
                        arr[i]--;
                    }
                }

                command = Console.ReadLine();

            }

            Console.WriteLine(string.Join(", ", arr));
        }
    }
}