Obtain different combinations from sets

Question

I have distinct sets identified by some names against which there are values. I use construct like Dictionary<string, List<string>> to store such entities. As my output I need all possible combinations of values that can be generated from this input syntax. In my attempt, I have devised an index based approach such that if the indices are correctly manipulated, I'd get required output of the form similar to the example. I understand that it might use recursion but I'm not sure how to go about it. Is this a recognized problem? Please find code below:

using System;
using System.Collections.Generic;

namespace Rextester
{
    public class Program
    {
        private static Dictionary<string, string> dataAtIndex(Dictionary<string, List<string>> iArgs, Dictionary<string, int> iArgIndex)
        {
            Dictionary<string, string> oConditionKeys = new Dictionary<string, string>();

            foreach (var vArgName in iArgs.Keys)
            {
                int index = iArgIndex[vArgName];
                string argValue = iArgs[vArgName][index];
                oConditionKeys.Add(vArgName, argValue);
            }

            return oConditionKeys;
        }

        private static void testFunc(Dictionary<string, List<string>> iArgs, ref List<Dictionary<string, string>> oListSelectKeys)
        {
            Dictionary<string, int> argIndex = new Dictionary<string, int>();
            foreach (var vArgName in iArgs.Keys)
            {
                argIndex.Add(vArgName, 0);
            }

            oListSelectKeys.Add(dataAtIndex(iArgs, argIndex));
        }


        public static void Main(string[] mainargs)
        {
            Dictionary<string, List<string>> args = new Dictionary<string, List<string>>();

            List<string> listArgData1 = new List<string>();
            listArgData1.Add("1=>Arg0");
            listArgData1.Add("1=>Arg1");
            listArgData1.Add("1=>Arg2");

            List<string> listArgData2 = new List<string>();
            listArgData2.Add("2=>Arg0");
            listArgData2.Add("2=>Arg1");

            List<string> listArgData3 = new List<string>();
            listArgData3.Add("3=>Arg0");
            listArgData3.Add("3=>Arg1");
            listArgData3.Add("3=>Arg2");
            listArgData3.Add("3=>Arg3");

            args.Add("Param1", listArgData1);
            args.Add("Param2", listArgData2);
            args.Add("Param3", listArgData3);

            Console.WriteLine("Input Data : ");
            foreach(var vKey in args.Keys) {
                Console.Write(vKey + " : ");
                foreach(var vData in args[vKey]) {
                    Console.Write(vData + " ");
                }
                Console.WriteLine();
            }
            Console.WriteLine();

            List<Dictionary<string, string>> listSelectKeys = new List<Dictionary<string, string>>();
            testFunc(args, ref listSelectKeys);

            int count = 0;
            Console.WriteLine("Output Data : ");
            foreach(var vElem in listSelectKeys) {
                Console.Write(count++ + " : ");
                foreach(var vKey in vElem.Keys) {
                    Console.Write("(" + vKey + ", " + vElem[vKey] + ") ");
                }
                Console.WriteLine();
            }
        }
    }
}

Output should be like:

0 : (Param1, 1=>Arg0) (Param2, 2=>Arg0) (Param3, 3=>Arg0)
1 : (Param1, 1=>Arg0) (Param2, 2=>Arg0) (Param3, 3=>Arg1)
2 : (Param1, 1=>Arg0) (Param2, 2=>Arg0) (Param3, 3=>Arg2)
...
n : (Param1, 1=>Arg2) (Param2, 2=>Arg1) (Param3, 3=>Arg3)

Thanks!

Answer 1

Finally got it to work...:) I used some looped recursion.:) Here you go:

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

namespace Rextester
{
    public class Program
    {
        private static Dictionary<string, string> dataAtIndex(Dictionary<string, List<string>> iArgs, Dictionary<string, int> iArgIndex)
        {
            Dictionary<string, string> oConditionKeys = new Dictionary<string, string>();

            foreach (var vArgName in iArgs.Keys)
            {
                int index = iArgIndex[vArgName];
                string argValue = iArgs[vArgName][index];
                oConditionKeys.Add(vArgName, argValue);
            }

            return oConditionKeys;
        }

        private static void generateArgIndexList(Dictionary<string, List<string>> iArgs, Dictionary<string, int> iArgIndex, ref List<Dictionary<string, int>> oListArgIndices)
        {
            if(iArgs.Count > 0)
            {
                string firstArgName = iArgs.First().Key;

                Dictionary<string, List<string>> newArgs = new Dictionary<string, List<string>>(iArgs);
                Dictionary<string, int> tmpArgInd = iArgIndex;
                while (tmpArgInd[firstArgName] < iArgs[firstArgName].Count)
                {
                    string lastArgName = newArgs.Last().Key;
                    if (tmpArgInd[lastArgName] < iArgs[lastArgName].Count)
                    {
                        oListArgIndices.Add(new Dictionary<string, int>(tmpArgInd));
                        ++tmpArgInd[lastArgName];
                    }
                    else
                    {
                        tmpArgInd[lastArgName] = 0;
                        newArgs.Remove(lastArgName);
                        lastArgName = newArgs.Last().Key;
                        if (tmpArgInd[lastArgName] < iArgs[lastArgName].Count)
                        {
                            ++tmpArgInd[lastArgName];
                            if (tmpArgInd[lastArgName] < iArgs[lastArgName].Count)
                                generateArgIndexList(iArgs, tmpArgInd, ref oListArgIndices);
                        }
                    }
                }
            }
        }

        private static void testFunc(Dictionary<string, List<string>> iArgs, ref List<Dictionary<string, string>> oListConditionKeys)
        {
            Dictionary<string, int> argIndex = new Dictionary<string, int>();
            foreach (var vArgName in iArgs.Keys)
            {
                argIndex.Add(vArgName, 0);
            }

            List<Dictionary<string, int>> listArgIndices = new List<Dictionary<string, int>>();
            generateArgIndexList(iArgs, argIndex, ref listArgIndices);
            foreach(var vArgIndex in listArgIndices)
            {
                oListConditionKeys.Add(dataAtIndex(iArgs, vArgIndex));
            }
        }


        public static void Main(string[] mainargs)
        {
            Dictionary<string, List<string>> args = new Dictionary<string, List<string>>();

            List<string> listArgData1 = new List<string>();
            listArgData1.Add("1=>Arg0");
            listArgData1.Add("1=>Arg1");
            listArgData1.Add("1=>Arg2");

            List<string> listArgData2 = new List<string>();
            listArgData2.Add("2=>Arg0");
            listArgData2.Add("2=>Arg1");

            List<string> listArgData3 = new List<string>();
            listArgData3.Add("3=>Arg0");
            listArgData3.Add("3=>Arg1");
            listArgData3.Add("3=>Arg2");
            listArgData3.Add("3=>Arg3");

            args.Add("Param1", listArgData1);
            args.Add("Param2", listArgData2);
            args.Add("Param3", listArgData3);

            Console.WriteLine("Input Data : ");
            foreach(var vKey in args.Keys) {
                Console.Write(vKey + " : ");
                foreach(var vData in args[vKey]) {
                    Console.Write(vData + " ");
                }
                Console.WriteLine();
            }
            Console.WriteLine();

            List<Dictionary<string, string>> listSelectKeys = new List<Dictionary<string, string>>();
            testFunc(args, ref listSelectKeys);

            int count = 0;
            Console.WriteLine("Output Data : ");
            foreach(var vElem in listSelectKeys) {
                Console.Write(count++ + " : ");
                foreach(var vKey in vElem.Keys) {
                    Console.Write("(" + vKey + ", " + vElem[vKey] + ") ");
                }
                Console.WriteLine();
            }
        }
    }
}