{ "data": { "question": { "questionId": "2198", "questionFrontendId": "2076", "boundTopicId": null, "title": "Process Restricted Friend Requests", "titleSlug": "process-restricted-friend-requests", "content": "

You are given an integer n indicating the number of people in a network. Each person is labeled from 0 to n - 1.

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You are also given a 0-indexed 2D integer array restrictions, where restrictions[i] = [xi, yi] means that person xi and person yi cannot become friends, either directly or indirectly through other people.

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Initially, no one is friends with each other. You are given a list of friend requests as a 0-indexed 2D integer array requests, where requests[j] = [uj, vj] is a friend request between person uj and person vj.

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A friend request is successful if uj and vj can be friends. Each friend request is processed in the given order (i.e., requests[j] occurs before requests[j + 1]), and upon a successful request, uj and vj become direct friends for all future friend requests.

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Return a boolean array result, where each result[j] is true if the jth friend request is successful or false if it is not.

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Note: If uj and vj are already direct friends, the request is still successful.

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Example 1:

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\nInput: n = 3, restrictions = [[0,1]], requests = [[0,2],[2,1]]\nOutput: [true,false]\nExplanation:\nRequest 0: Person 0 and person 2 can be friends, so they become direct friends. \nRequest 1: Person 2 and person 1 cannot be friends since person 0 and person 1 would be indirect friends (1--2--0).\n
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Example 2:

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\nInput: n = 3, restrictions = [[0,1]], requests = [[1,2],[0,2]]\nOutput: [true,false]\nExplanation:\nRequest 0: Person 1 and person 2 can be friends, so they become direct friends.\nRequest 1: Person 0 and person 2 cannot be friends since person 0 and person 1 would be indirect friends (0--2--1).\n
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Example 3:

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\nInput: n = 5, restrictions = [[0,1],[1,2],[2,3]], requests = [[0,4],[1,2],[3,1],[3,4]]\nOutput: [true,false,true,false]\nExplanation:\nRequest 0: Person 0 and person 4 can be friends, so they become direct friends.\nRequest 1: Person 1 and person 2 cannot be friends since they are directly restricted.\nRequest 2: Person 3 and person 1 can be friends, so they become direct friends.\nRequest 3: Person 3 and person 4 cannot be friends since person 0 and person 1 would be indirect friends (0--4--3--1).\n
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Constraints:

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