Algorithms - 5. Generating Combinations

using System;
using System.Linq;

namespace Recursion
{
    class Program
    {
        static void Main(string[] args)
        {
            var numbers = Console.ReadLine().Split().Select(int.Parse).ToArray();
            var k = int.Parse(Console.ReadLine());
            var set = new int[k];

            GenerateCombinations(numbers, set, 0, 0);
        }

        static void GenerateCombinations(int[] numbers, int[] set, int index, int border)
        {
            if (index >= set.Length)
            {
                Console.WriteLine(string.Join(" ", set));
            }

            else
            {
                for (int i = border; i < numbers.Length; i++)
                {
                    set[index] = numbers[i];
                    GenerateCombinations(numbers, set, index + 1, i + 1);
                }
            }
        }
    }
}