{ "data": { "question": { "questionId": "1159", "questionFrontendId": "1081", "boundTopicId": null, "title": "Smallest Subsequence of Distinct Characters", "titleSlug": "smallest-subsequence-of-distinct-characters", "content": "

Given a string s, return the lexicographically smallest subsequence of s that contains all the distinct characters of s exactly once.

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Example 1:

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\nInput: s = "bcabc"\nOutput: "abc"\n
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Example 2:

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\nInput: s = "cbacdcbc"\nOutput: "acdb"\n
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Constraints:

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

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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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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 gnu99 standard.

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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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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