How to get distinct characters?

Question

I have a code like

string code = \"AABBDDCCRRFF\";

In this code, I want to retrieve only distinct characters

The Output should be l

Answer 1

string code = "AABBDDCCRRFF";
string answer = new String(code.Distinct().ToArray());

Answer 2

How about in linq:

var str = "AABBCCDDDDDDEEEEEFFF";
var unique = str.ToCharArray().Distinct();
Console.WriteLine("Answer: {0}.", string.Join(string.Empty, unique));

Answer 3

You can do this as follows

var s = "AABBDDCCRRFF";
var result = s.Distinct();
var distinct = result.Aggregate(string.Empty, (current, c) => current + c.ToString());
Console.WriteLine(distinct);