using System;
using System.Collections.Generic;
internal class Program
{
public static HashSet<char> makeset(string str) {
char[] arr = str.ToCharArray();
var hset = new HashSet<char>(arr);
return hset;
}
public static void Main(string[] args)
{
string str = "CSharp Programming";
Console.WriteLine(string.Join(",", makeset(str)));
}
}
/*
run:
C,S,h,a,r,p, ,P,o,g,m,i,n
*/