How can you remove duplicate characters in a string?

Question

I have to implements a function that takes a string as an input and finds the non-duplicate character from this string.

So an an example is if I pass string str = "DHCD" it will return "DHC" or str2 = "KLKLHHMO" it will return "KLHMO"

Answer 1

A Linq approach:

public static string RemoveDuplicates(string input)
{
    return new string(input.ToCharArray().Distinct().ToArray());
}