{ "data": { "question": { "questionId": "151", "questionFrontendId": "151", "boundTopicId": null, "title": "Reverse Words in a String", "titleSlug": "reverse-words-in-a-string", "content": "

Given an input string s, reverse the order of the words.

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A word is defined as a sequence of non-space characters. The words in s will be separated by at least one space.

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Return a string of the words in reverse order concatenated by a single space.

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Note that s may contain leading or trailing spaces or multiple spaces between two words. The returned string should only have a single space separating the words. Do not include any extra spaces.

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Example 1:

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\nInput: s = "the sky is blue"\nOutput: "blue is sky the"\n
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Example 2:

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\nInput: s = "  hello world  "\nOutput: "world hello"\nExplanation: Your reversed string should not contain leading or trailing spaces.\n
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Example 3:

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\nInput: s = "a good   example"\nOutput: "example good a"\nExplanation: You need to reduce multiple spaces between two words to a single space in the reversed string.\n
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Constraints:

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Follow-up: If the string data type is mutable in your language, can you solve it in-place with O(1) extra space?

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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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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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Compiled with gcc 8.2 using the gnu11 standard.

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Your code is compiled with level one optimization (-O1). 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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3. Deleting an item in a hash:\\r\\n

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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Your code is run with --harmony flag, enabling new ES6 features.

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lodash.js library is included by default.

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For Priority Queue / Queue data structures, you may use 5.3.0 version of datastructures-js/priority-queue and 4.2.1 version of datastructures-js/queue.

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Ruby 3.1

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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms

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Swift 5.5.2.

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Go 1.21

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Python 3.10.

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Kotlin 1.9.0.

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PHP 8.1.

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With bcmath module

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TypeScript 5.1.6, Node.js 16.13.2.

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Run with Racket 8.3.

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Dart 2.17.3

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