The Build Order

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

Domain

Python

Difficulty

medium

Seniority

L4

Problem

A build system has `n` modules numbered `0` to `n-1` and a list of `edges`, where each `[a, b]` pair means module `a` can only be built once module `b` has been built. Return an order in which every module can be built, and when more than one module is ready at the same moment, take the lowest-numbered one first. If the dependencies loop so that no valid order exists, return an empty list.

Summary

Some tasks must wait for others to finish first.

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