A easy Python interview practice problem on DataDriven. Write and execute real python code with instant grading.

Domain

Python

Difficulty

easy

Seniority

L3

Problem

Given a list that may contain None values, return a list of the same length where each None is replaced by the most recent prior non-None value. If a None appears before any non-None value has been seen, leave it as None.

Summary

Patch the gaps in a noisy sensor stream.

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