{ "data": { "question": { "questionId": "387", "questionFrontendId": "387", "boundTopicId": null, "title": "First Unique Character in a String", "titleSlug": "first-unique-character-in-a-string", "content": "

Given a string s, find the first non-repeating character in it and return its index. If it does not exist, return -1.

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Example 1:

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Input: s = \"leetcode\"\nOutput: 0\n

Example 2:

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Input: s = \"loveleetcode\"\nOutput: 2\n

Example 3:

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Input: s = \"aabb\"\nOutput: -1\n
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Constraints:

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Python 2.7.12.

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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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Python 3.10.

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