Remove duplicated elements from a List<String>

Question

I would like to remove the duplicate elements from a List. Some elements of the list looks like this:

Book  23
Book  22
Book  19
Notebook 22
Notebook 19
Pen 23
Pen 22
Pen 19

To get rid of duplicate elements i've done this:

List<String> nodup = dup.Distinct().ToList();

I would like to keep in the list just

Book 23
Notebook 22
Pen 23

How can i do that ?

Answer 1

you can do someting like

string firstElement = dup.Distinct().ToList().First();

and add it to another list if you want.

Answer 2

It's not 100% clear what you want here - however...

If you want to keep the "largest" number in the list, you could do:

List<string> noDup = dup.Select(s => s.Split(new[] {' '}, StringSplitOptions.RemoveEmptyEntries)
        .Select(p => new { Name=p[0], Val=int.Parse(p[1]) })
        .GroupBy(p => p.Name)
        .Select(g => string.Join(" ", g.Key, g.Max().ToString()))
        .ToList();

This would transform the List<string> by parsing the numeric portion into a number, taking the max per item, and creating the output string as you have specified.