{ "data": { "question": { "questionId": "2128", "questionFrontendId": "2000", "boundTopicId": null, "title": "Reverse Prefix of Word", "titleSlug": "reverse-prefix-of-word", "content": "

Given a 0-indexed string word and a character ch, reverse the segment of word that starts at index 0 and ends at the index of the first occurrence of ch (inclusive). If the character ch does not exist in word, do nothing.

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Return the resulting string.

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Example 1:

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\nInput: word = "abcdefd", ch = "d"\nOutput: "dcbaefd"\nExplanation: The first occurrence of "d" is at index 3. \nReverse the part of word from 0 to 3 (inclusive), the resulting string is "dcbaefd".\n
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Example 2:

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\nInput: word = "xyxzxe", ch = "z"\nOutput: "zxyxxe"\nExplanation: The first and only occurrence of "z" is at index 3.\nReverse the part of word from 0 to 3 (inclusive), the resulting string is "zxyxxe".\n
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Example 3:

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\nInput: word = "abcd", ch = "z"\nOutput: "abcd"\nExplanation: "z" does not exist in word.\nYou should not do any reverse operation, the resulting string is "abcd".\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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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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C# 10 with .NET 6 runtime

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

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Node.js 16.13.2.

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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 1.17.6.

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Python 3.10.

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