How to remove same combination (same number but diffrent order) on list?

Question

I have a string List like this

code

    List<string> MyList = new List<string>();
    MyList.Add("153");
    MyList.Add("112");
    MyList.Add("531");
    MyList.Add("675");
    MyList.Add("889");
    MyList.Add("351");

code
I want only one combination of (153) or (531) or (351).
The output should be
153
112
675
889

Edit:I know if I want to remove duplicate i should use MyList =MyList.Distinct(); as suggested in another duplicate Remove duplicates from a List<T> in C# of my previous (now deleted) question. but the problem is (153),(531),(351) are not duplicate.

Obviously I read documentation and it shows some alternative version of Distinct with some sort of "comparer", but example there is for objects and I have strings.

When I asked the same question about an hour ago it was closed by ... as duplicate of https://stackoverflow.com/a/50177/477420 which clearly not applicable to me at all - I don't know why I would ever compare two strings as sequences of characters ignoring order. I still tried that code and it returned "true" for one of the cases I have:

"153".OrderBy(i => i).SequenceEqual("531".OrderBy(i => i))

Even then it does not look useful.

You forgot to explain why [the other](https://stackoverflow.com/questions/50098/comparing-two-collections-for-equality-irrespective-of-the-order-of-items-in-the) duplicate did not help. (Note that deleting your posts is not recommended, and will lower chances to get any answers as everyone would expect that you will delete the question as soon as you get an answer). — Alexei Levenkov, Jun 16 '22 at 21:20
The previous question locked because other didn’t understand it but I added more detail to this one. Why I would delete the question if I got answer this will not help people — James DEV, Jun 16 '22 at 21:27

score 1 · Accepted Answer · answered Jun 16 '22 at 22:49

A quick and a bit dirty way of getting what you wanted, without custom comparer and with items in original order:

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

public class Program
{
    public static void Main()
    {
        List<string> MyList = new List<string>();
        MyList.Add("153");
        MyList.Add("112");
        MyList.Add("531");
        MyList.Add("675");
        MyList.Add("889");
        MyList.Add("351");
        
        int i = 0;
        var ac = new Dictionary<int, string>();
        var res = new Dictionary<int, string>(); 

        foreach (var a in MyList)
        {
            res.Add(i, a);
            var ou = a.ToArray();
            Array.Sort(ou);
            ac.Add(i, new String(ou));
            i++;
        }

        var filteredDictionary = ac.GroupBy(s => s.Value).Where(gr => gr.Any()).Select(g => g.First()).ToDictionary(kvp => kvp.Key, kvp => kvp.Value);
        var ret = res.Where(x => filteredDictionary.ContainsKey(x.Key)).Select(x => x.Value);
        foreach (var c in ret)
        {
            Console.WriteLine(c);
        }
    }
}

Result:

Fiddle: https://dotnetfiddle.net/#&togetherjs=1dgVkP8AGf

This does not contain any safety checks, nor does it handle strings that are not 'numbers', but will work with your example leaving first occurrence of given combination.

How to remove same combination (same number but diffrent order) on list?

1 Answers1