02.1.21.NumberCombinations

using System;

class NumberCombinations
{
    static void Combinations(int index, int[] vector, int numbersLength, int start)
    {
        if (index == -1)
        {
            Print(vector);
        }
        else
        {
            for (int i = start; i <= numbersLength; i++)
            {
                vector[index] = i;
                Combinations(index - 1, vector, (numbersLength), (i + 1));
            }
        }
    }
    static void Print(int[] vector)
    {
        foreach (int i in vector)
        {
            Console.Write("{0} ", i);
        }
        Console.WriteLine();
    }

    static void Main()
    {
        Console.Write("Please enter the amount of the numbers 1...N, N = ");
        int numbersAmount = int.Parse(Console.ReadLine());
        Console.Write("Please enter the amount of the combinations K = ");
        int combinationsAmount = int.Parse(Console.ReadLine());
        int[] vector = new int[combinationsAmount];
        Combinations(combinationsAmount - 1, vector, numbersAmount, 1);
    }
}