All Permutations [1..N] with Heap's Algorithm

using System;
using System.Collections.Generic;
using System.Linq;

class PrintAllPermutationsOfInterval1ToNHeapAlg
{
  static void HeapPermute(int[] arrayOfPermutes, int length, List<string> CurrentList)//The heap algorythm for ermutations
  {
    int swapBuffer = 0; //A buffer used to swap the elements in the array

    if (length == 1) //If length has reached 1 it is time to record the currentList that contains one of the permutations
    {
      string currentPermutation = ""; //Create a string to hold the current positions of the numbers
      for (int i = 0; i < arrayOfPermutes.Length; i++)
      {
        currentPermutation += arrayOfPermutes[i] + " ";
      }
      CurrentList.Add(currentPermutation); //Add the string to a list to print it later
    }
    else
    {
      for (int i = 0; i < length; i++) //If we are still in the recursion
      {
        HeapPermute(arrayOfPermutes, length - 1, CurrentList); //Recursion with length minus one.

        if (length % 2 == 1) //Heap algorithm: if the remainder is 1-st we swap the first element with the element that has lenght-1
        {
          swapBuffer = arrayOfPermutes[0];
          arrayOfPermutes[0] = arrayOfPermutes[length - 1];
          arrayOfPermutes[length - 1] = swapBuffer;
        }
        else//Heap algorithm: if the remainder is not 1 we swap the i-th element with the element that has lenght-1
        {
          swapBuffer = arrayOfPermutes[i];
          arrayOfPermutes[i] = arrayOfPermutes[length - 1];
          arrayOfPermutes[length - 1] = swapBuffer;
        }
      }
    }
  }

  static void Main()
  {
    int numN = 4; //The number to permute! Be careful even for 10 it takes a lot of time! It print numN! permutations!
    List<string> CurrentList = new List<string>(); //A list used to store and later print the current permutation
    int[] arrayOfNumbers = new int[numN]; //The starting array of numbers

    for (int i = 0; i < numN; i++)//Generates and fills the elemnets of the array from 1 to numN
    {
      arrayOfNumbers[i] = i + 1;
    }

    //Do the Heap algorithm on the array to generate the permutations
    HeapPermute(arrayOfNumbers, numN, CurrentList);

    //Print the resulting list
    for (int i = 0; i < CurrentList.Count; i++)
    {
      Console.WriteLine(CurrentList[i]);
    }
  }
}