{ "data": { "question": { "questionId": "2096", "questionFrontendId": "1964", "boundTopicId": null, "title": "Find the Longest Valid Obstacle Course at Each Position", "titleSlug": "find-the-longest-valid-obstacle-course-at-each-position", "content": "

You want to build some obstacle courses. You are given a 0-indexed integer array obstacles of length n, where obstacles[i] describes the height of the ith obstacle.

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For every index i between 0 and n - 1 (inclusive), find the length of the longest obstacle course in obstacles such that:

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Return an array ans of length n, where ans[i] is the length of the longest obstacle course for index i as described above.

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Example 1:

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\nInput: obstacles = [1,2,3,2]\nOutput: [1,2,3,3]\nExplanation: The longest valid obstacle course at each position is:\n- i = 0: [1], [1] has length 1.\n- i = 1: [1,2], [1,2] has length 2.\n- i = 2: [1,2,3], [1,2,3] has length 3.\n- i = 3: [1,2,3,2], [1,2,2] has length 3.\n
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Example 2:

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\nInput: obstacles = [2,2,1]\nOutput: [1,2,1]\nExplanation: The longest valid obstacle course at each position is:\n- i = 0: [2], [2] has length 1.\n- i = 1: [2,2], [2,2] has length 2.\n- i = 2: [2,2,1], [1] has length 1.\n
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Example 3:

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\nInput: obstacles = [3,1,5,6,4,2]\nOutput: [1,1,2,3,2,2]\nExplanation: The longest valid obstacle course at each position is:\n- i = 0: [3], [3] has length 1.\n- i = 1: [3,1], [1] has length 1.\n- i = 2: [3,1,5], [3,5] has length 2. [1,5] is also valid.\n- i = 3: [3,1,5,6], [3,5,6] has length 3. [1,5,6] is also valid.\n- i = 4: [3,1,5,6,4], [3,4] has length 2. [1,4] is also valid.\n- i = 5: [3,1,5,6,4,2], [1,2] has length 2.\n
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Constraints:

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