DIY: First Bad Version

Solve the interview question "First Bad Version" in this lesson.

Problem statement

The latest version of a software product fails the quality check. Since each version is developed upon the previous one, all the versions created after a bad version are also considered bad. Suppose you have n versions with the following IDs:[1, 2, ..., n]. Your task is to find the first bad one, which is causing all the later ones to be bad.

Consider that you have the access to an API call, VersionControl.isBadVersion(), that returns true if the input is the ID of a bad version. You have to implement a solution with the minimum number of API calls.

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