{ "data": { "question": { "questionId": "2048", "questionFrontendId": "1920", "boundTopicId": null, "title": "Build Array from Permutation", "titleSlug": "build-array-from-permutation", "content": "

Given a zero-based permutation nums (0-indexed), build an array ans of the same length where ans[i] = nums[nums[i]] for each 0 <= i < nums.length and return it.

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A zero-based permutation nums is an array of distinct integers from 0 to nums.length - 1 (inclusive).

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Example 1:

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\nInput: nums = [0,2,1,5,3,4]\nOutput: [0,1,2,4,5,3]\nExplanation: The array ans is built as follows: \nans = [nums[nums[0]], nums[nums[1]], nums[nums[2]], nums[nums[3]], nums[nums[4]], nums[nums[5]]]\n    = [nums[0], nums[2], nums[1], nums[5], nums[3], nums[4]]\n    = [0,1,2,4,5,3]
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Example 2:

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\nInput: nums = [5,0,1,2,3,4]\nOutput: [4,5,0,1,2,3]\nExplanation: The array ans is built as follows:\nans = [nums[nums[0]], nums[nums[1]], nums[nums[2]], nums[nums[3]], nums[nums[4]], nums[nums[5]]]\n    = [nums[5], nums[0], nums[1], nums[2], nums[3], nums[4]]\n    = [4,5,0,1,2,3]
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Constraints:

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Follow-up: Can you solve it without using an extra space (i.e., O(1) memory)?

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