{ "data": { "question": { "questionId": "991", "questionFrontendId": "954", "boundTopicId": null, "title": "Array of Doubled Pairs", "titleSlug": "array-of-doubled-pairs", "content": "

Given an integer array of even length arr, return true if it is possible to reorder arr such that arr[2 * i + 1] = 2 * arr[2 * i] for every 0 <= i < len(arr) / 2, or false otherwise.

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Example 1:

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\nInput: arr = [3,1,3,6]\nOutput: false\n
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Example 2:

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\nInput: arr = [2,1,2,6]\nOutput: false\n
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Example 3:

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\nInput: arr = [4,-2,2,-4]\nOutput: true\nExplanation: We can take two groups, [-2,-4] and [2,4] to form [-2,-4,2,4] or [2,4,-2,-4].\n
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Constraints:

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Compiled with clang 11 using the latest C++ 17 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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Includes Pair class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.

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Python 2.7.12.

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C# 10 with .NET 6 runtime

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