{ "data": { "question": { "questionId": "2571", "questionFrontendId": "2485", "boundTopicId": null, "title": "Find the Pivot Integer", "titleSlug": "find-the-pivot-integer", "content": "

Given a positive integer n, find the pivot integer x such that:

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Return the pivot integer x. If no such integer exists, return -1. It is guaranteed that there will be at most one pivot index for the given input.

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Example 1:

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\nInput: n = 8\nOutput: 6\nExplanation: 6 is the pivot integer since: 1 + 2 + 3 + 4 + 5 + 6 = 6 + 7 + 8 = 21.\n
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Example 2:

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\nInput: n = 1\nOutput: 1\nExplanation: 1 is the pivot integer since: 1 = 1.\n
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Example 3:

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\nInput: n = 4\nOutput: -1\nExplanation: It can be proved that no such integer exist.\n
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Constraints:

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