One Step Behind

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

Domain

Python

Difficulty

medium

Seniority

L3

Problem

You're aligning a stream of sensor readings so each one can sit beside the reading that came just before it. Return a list the same length as the input, where each slot carries its predecessor's value.

Summary

What came before this row?

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