{ "data": { "question": { "questionId": "1835", "questionFrontendId": "1734", "boundTopicId": null, "title": "Decode XORed Permutation", "titleSlug": "decode-xored-permutation", "content": "

There is an integer array perm that is a permutation of the first n positive integers, where n is always odd.

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It was encoded into another integer array encoded of length n - 1, such that encoded[i] = perm[i] XOR perm[i + 1]. For example, if perm = [1,3,2], then encoded = [2,1].

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Given the encoded array, return the original array perm. It is guaranteed that the answer exists and is unique.

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Example 1:

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\nInput: encoded = [3,1]\nOutput: [1,2,3]\nExplanation: If perm = [1,2,3], then encoded = [1 XOR 2,2 XOR 3] = [3,1]\n
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Example 2:

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\nInput: encoded = [6,5,4,6]\nOutput: [2,4,1,5,3]\n
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Constraints:

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Compiled with clang 11 using the latest C++ 17 standard.

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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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Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.

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

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Note that Python 2.7 will not be maintained past 2020. For the latest Python, please choose Python3 instead.

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C# 10 with .NET 6 runtime

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Your code is compiled with debug flag enabled (/debug).

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Ruby 3.1

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Swift 5.5.2.

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Go 1.17.6.

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Python 3.10.

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