{ "data": { "question": { "questionId": "278", "questionFrontendId": "278", "boundTopicId": null, "title": "First Bad Version", "titleSlug": "first-bad-version", "content": "

You are a product manager and currently leading a team to develop a new product. Unfortunately, the latest version of your product fails the quality check. Since each version is developed based on the previous version, all the versions after a bad version are also bad.

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Suppose you have n versions [1, 2, ..., n] and you want to find out the first bad one, which causes all the following ones to be bad.

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You are given an API bool isBadVersion(version) which returns whether version is bad. Implement a function to find the first bad version. You should minimize the number of calls to the API.

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Example 1:

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\nInput: n = 5, bad = 4\nOutput: 4\nExplanation:\ncall isBadVersion(3) -> false\ncall isBadVersion(5) -> true\ncall isBadVersion(4) -> true\nThen 4 is the first bad version.\n
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Example 2:

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\nInput: n = 1, bad = 1\nOutput: 1\n
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Constraints:

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Compiled with clang 11 using the latest C++ 20 standard.

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Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

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Most standard library headers are already included automatically for your convenience.

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Python 2.7.12.

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For Map/TreeMap data structure, you may use sortedcontainers library.

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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