static void Main()
{
var elementsCount = int.Parse(Console.ReadLine());
var elements = Enumerable.Range(1, elementsCount).ToArray();
Permutations.PermutationWrite(elements, 0);
}
private static void PermutationWrite(int[] range, int currentIndex)
{
if (range.Length <= currentIndex)
{
// Full permutation found -> print it.
Console.WriteLine(string.Join(" ", range));
}
else
{
// Find the end of the array.
Permutations.PermutationWrite(range, currentIndex + 1);
for (int swapWithIndex = currentIndex + 1; swapWithIndex < range.Length; swapWithIndex++)
{
// Swap the current element with each of the element following it.
Permutations.SwapElements(range, currentIndex, swapWithIndex);
// Find each of the permutation for the current configuration.
Permutations.PermutationWrite(range, currentIndex + 1);
// Swap the elements back.
Permutations.SwapElements(range, currentIndex, swapWithIndex);
}
}
}