如何在2个不同大小的字符串数组中查找所有可能的字符串组合

Question

I am running into a peculiar problem of which i couldn't find any solution after long search. Here is my question:

I have two String Arrays:

   var arr1 = new[] { "UserId", "BookId", "BookStoreId", "Appid" };
   var arr2 = new[] {"Same", "Unique", "Repetitive"};

I want Result with all possible combinations like:

Result (Should be in tabular format):

Columns- UserId BookId BookStoreId Appid

• Row1 Same Same Same Same
• Row2 Same Same Same Unique

• Row3 Same Same Same Repetitive

• Row4 Same Same Unique Same

• Row5 Same Same Repetitive Same

• Row6 Same Same Unique Unique

• Row6 Same Same Unique Repetitive
• Row7 Same Same Repetitive Unique

• Row8 Same Same Repetitive Repetitive

• Row9 Same Unique Same Same

• Row10 Same Unique Unique Same
• Row11 Same Repetitive Same Same and so on...

Rows and Columns are only for notation purpose.

I hope my question is clear now.

I Should create 64 Unique Combinations.

I have tried lots of ways including Cartesian products but that didnt solved my problem.

Answer 1

Seems to you need a Combinations With Repetitions. Check this answer https://stackoverflow.com/a/25824818/1007620

Summary:

static IEnumerable<String> CombinationsWithRepition(IEnumerable<string> input, int length)
{
    if (length <= 0)
        yield return "";
    else
    {
        foreach(var i in input)
            foreach(var c in CombinationsWithRepition(input, length-1))
                yield return i + ',' + c;
    }
}

Then

string[] items = {"UserId", "BookId", "BookStoreId", "Appid", "Same", "Unique", "Repetitive"};
foreach (var c in CombinationsWithRepition(items, 4))
    Console.WriteLine (c);

Result https://pastebin.com/2hCbA1XJ