Unique Character Coding | Dataford Interview Questions

Given a string, find the first character that is unique, meaning it appears only once.

Implement first_unique_char(s) to return the character itself. Return an empty string if no character appears exactly once. Treat characters according to Python string iteration.

Signature: def first_unique_char(s):

Constraints

0 <= len(s) <= 10^5
s may contain any characters supported by Python strings
Return the character itself, not its index
Return an empty string when no unique character exists

Function Signature

def first_unique_char(s):

Your question is Unique Character Coding. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem