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.
One example is below.
Q: abCCdDDgGGhi
A: abCdDgGhi
Rationale: The input string has 3 duplicate characters and the resulting output string has no duplicate characters.
Q: NOXIdIppfrgUFWCgdPvNqsZOjPxB
A:
NOXIdpfrgUFWCPvqsZjxB