How to get all possible combinations ?

I have n numbers of array contains n number of data.

I want to write out all the possible combinations.

For ex:-

var list1 = new List { "A", "B", "C", "D" };

var list2 = new List { "10", "20", "30", "40", "50" };

var list3 = new List { "ABC", "DEF", "GHI", "JKL" };

Possible outputs :

A-10-ABC

A-10-DEF

A-10-GHI

A-10-JKL

A-20-ABC

A-20-DEF

A-20-GHI

A-20-JKL

A-30-ABC

A-30-DEF

A-30-GHI

A-30-JKL

........ and so on

The actual problem is the number of list variable is not constant, therefore I can't just write a fixed amount of nested loop.

Hope someone can help me....

Hey try this

public static IEnumerable> DynamicLoop(IList> data)
{
var count = data.Count;
var loopIndex = count - 1;
var counters = new int[count];
var bounds = data.Select(x => x.Count).ToArray();
do
{
yield return Enumerable.Range(0, count).Select(x => data[x][counters[x]]);
} while (LoopIncrement(counters, bounds, ref loopIndex));
}
private static bool LoopIncrement(IList<int> counters, IList<int> bounds, ref int loopIndex)
{
if (loopIndex < 0)
return false;
counters[loopIndex] = counters[loopIndex] + 1;
var result = true;
if (counters[loopIndex] >= bounds[loopIndex])
{
counters[loopIndex] = 0;
loopIndex--;
result = LoopIncrement(counters, bounds, ref loopIndex);
loopIndex++;
}
return result;
}
static void Main(string[] args)
{
var list1 = new List<string> { "AMIT", "BISWANATH", "CHINMAYEE", "DEEPAK" };
var list2 = new List<string> { "BHUBANESWAR", "BOLANGIR", "ANGUL", "CUTTACK", "BARIPADA" };
var list3 = new List<string> { "ODISHA" };
var data = new Liststring>>
{
list1,
list2,
list3
};
foreach (var item in DynamicLoop(data).Select(x => string.Join(" - ", x)))
Console.WriteLine(item);
Console.ReadLine();
}

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