Code RoomFirst submission per student
EasyPrep Room Coding #406

First submission per student

CodingAlgorithms & data structuresEntry–Mid~11 min

An online quiz logs every submission in arrival order as rows "student,answer". Only a student's FIRST submission counts; later ones are ignored. Return the counting rows — one per student, the first they sent — in the order those students first appeared. Example: ["ava,B", "raj,C", "ava,D"] gives ["ava,B", "raj,C"].

Implement
first_submissions(rows: list[str]) → list[str]
Examples
in[["ava,B","raj,C","ava,D"]]out["ava,B","raj,C"]
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

0:00 of about 11 min
InputExpectedGot
[["ava,B","raj,C","ava,D"]]["ava,B","raj,C"]not run yetsample