In this task, you are given a string of characters. You need to remove duplicate characters from the string if any, and return the resulting string.

Ex Input:
HEWadwrxiOMKskgGqlAALNHb

Ex Output:
HEWadwrxiOMKskgGqlALNb


Ex Input:
dNrnbueSGYhdKguSDTykRjSwVY

Ex Output:
dNrnbueSGYhKgDTykRjwV


Ex Input:
fGXjcfpSTtIbBsYCrewFkcIH

Ex Output:

fGXjcpSTtIbBsYCrewFkH