First non-repeating character

Name: PyRun — Python Playground
Availability: InStock

EasyPattern: Strings

Write first_unique(s) returning the index of the first character that appears exactly once, or -1.

first_unique("leetcode")      ->  0
first_unique("loveleetcode")  ->  2
first_unique("aabb")          ->  -1

solution.py

Stuck on the idea itself? The strings lesson walks through the pattern from scratch.

loading…