{ "data": { "question": { "questionId": "2213", "questionFrontendId": "2092", "boundTopicId": null, "title": "Find All People With Secret", "titleSlug": "find-all-people-with-secret", "content": "

You are given an integer n indicating there are n people numbered from 0 to n - 1. You are also given a 0-indexed 2D integer array meetings where meetings[i] = [xi, yi, timei] indicates that person xi and person yi have a meeting at timei. A person may attend multiple meetings at the same time. Finally, you are given an integer firstPerson.

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Person 0 has a secret and initially shares the secret with a person firstPerson at time 0. This secret is then shared every time a meeting takes place with a person that has the secret. More formally, for every meeting, if a person xi has the secret at timei, then they will share the secret with person yi, and vice versa.

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The secrets are shared instantaneously. That is, a person may receive the secret and share it with people in other meetings within the same time frame.

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Return a list of all the people that have the secret after all the meetings have taken place. You may return the answer in any order.

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Example 1:

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\nInput: n = 6, meetings = [[1,2,5],[2,3,8],[1,5,10]], firstPerson = 1\nOutput: [0,1,2,3,5]\nExplanation:\nAt time 0, person 0 shares the secret with person 1.\nAt time 5, person 1 shares the secret with person 2.\nAt time 8, person 2 shares the secret with person 3.\nAt time 10, person 1 shares the secret with person 5.​​​​\nThus, people 0, 1, 2, 3, and 5 know the secret after all the meetings.\n
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Example 2:

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\nInput: n = 4, meetings = [[3,1,3],[1,2,2],[0,3,3]], firstPerson = 3\nOutput: [0,1,3]\nExplanation:\nAt time 0, person 0 shares the secret with person 3.\nAt time 2, neither person 1 nor person 2 know the secret.\nAt time 3, person 3 shares the secret with person 0 and person 1.\nThus, people 0, 1, and 3 know the secret after all the meetings.\n
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Example 3:

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\nInput: n = 5, meetings = [[3,4,2],[1,2,1],[2,3,1]], firstPerson = 1\nOutput: [0,1,2,3,4]\nExplanation:\nAt time 0, person 0 shares the secret with person 1.\nAt time 1, person 1 shares the secret with person 2, and person 2 shares the secret with person 3.\nNote that person 2 can share the secret at the same time as receiving it.\nAt time 2, person 3 shares the secret with person 4.\nThus, people 0, 1, 2, 3, and 4 know the secret after all the meetings.\n
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Constraints:

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