Question

I am creating a forecasting application that will run simulations for various “modes” that a production plant is able to run. The plant can run in one mode per day, so I am writing a function that will add up the different modes chosen each day that best maximize the plant’s output and best aligns with the sales forecast numbers provided. This data will be loaded into an array of mode objects that will then be used to calculate the forecast output of the plant.

I have created the functions to do this, however, I need to make them recursive so that I am able to handle any number (within reason) of modes and work days (which varies based on production needs). Listed below is my code using for loops to simulate what I want to do. Can someone point me in the right direction in order to create a recursive function to replace the need for multiple for loops?

Where the method GetNumbers4 would be when there were four modes, and GetNumbers5 would be 5 modes. Int start would be the number of work days.

  private static void GetNumber4(int start)
    {
        int count = 0;
        int count1 = 0;          

        for (int i = 0; 0 <= start; i++)
        {
            for (int j = 0; j <= i; j++)
            {

                for (int k = 0; k <= j; k++)
                {
                    count++;

                     for (int l = 0; l <= i; l++)
                     {
                         count1 = l;
                     }

                     Console.WriteLine(start + " " + (count1 - j) + " " + (j - k) + " " + k);
                     count1 = 0;
                }  

            }
            start--;

        }
        Console.WriteLine(count);

    }

    private static void GetNumber5(int start)
    {
        int count = 0;
        int count1 = 0;

        for (int i = 0; 0 <= start; i++)
        {
            for (int j = 0; j <= i; j++)
            {

                for (int k = 0; k <= j; k++)
                {

                    for (int l = 0; l <= k; l++)
                    {
                        count++;
                        for (int m = 0; m <= i; m++)
                        {
                            count1 = m;
                        }
                        Console.WriteLine(start + " " + (count1 - j) + " " + (j - k) + " " + (k - l) + " " + l);
                        count1 = 0;
                    }

                }

            }
            start--;

        }
        Console.WriteLine(count);

    }

EDITED:

I think that it would be more helpful if I gave an example of what I was trying to do. For example, if a plant could run in three modes “A”, “B”, “C” and there were three work days, then the code will return the following results.

3  0  0
2  1  0
2  0  0
1  2  0
1  1  1
1  0  2
0  3  0
0  2  1
0  1  2
0  0  3

The series of numbers represent the three modes A B C. I will load these results into a Modes object that has the corresponding production rates. Doing it this way allows me to shortcut creating a list of every possible combination; it instead gives me a frequency of occurrence.

Building on one of the solutions already offered, I would like to do something like this.

    //Where Modes is a custom classs
    private static Modes GetNumberRecur(int start, int numberOfModes)
    {
        if (start < 0)
        {
            return Modes;

        }

        //Do work here
        GetNumberRecur(start - 1);
    }

Thanks to everyone who have already provided input.

Answer 1

Calling GetNumber(5, x) should yield the same result as GetNumber5(x):

static void GetNumber(int num, int max) {
    Console.WriteLine(GetNumber(num, max, ""));
}
static int GetNumber(int num, int max, string prefix) {
    if (num < 2) {
        Console.WriteLine(prefix + max);
        return 1;
    }
    else {
        int count = 0;
        for (int i = max; i >= 0; i--)
            count += GetNumber(num - 1, max - i, prefix + i + " ");
        return count;
    }
}