{ "data": { "question": { "questionId": "3326", "questionFrontendId": "3067", "boundTopicId": null, "title": "Count Pairs of Connectable Servers in a Weighted Tree Network", "titleSlug": "count-pairs-of-connectable-servers-in-a-weighted-tree-network", "content": "

You are given an unrooted weighted tree with n vertices representing servers numbered from 0 to n - 1, an array edges where edges[i] = [ai, bi, weighti] represents a bidirectional edge between vertices ai and bi of weight weighti. You are also given an integer signalSpeed.

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Two servers a and b are connectable through a server c if:

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Return an integer array count of length n where count[i] is the number of server pairs that are connectable through the server i.

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Example 1:

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\nInput: edges = [[0,1,1],[1,2,5],[2,3,13],[3,4,9],[4,5,2]], signalSpeed = 1\nOutput: [0,4,6,6,4,0]\nExplanation: Since signalSpeed is 1, count[c] is equal to the number of pairs of paths that start at c and do not share any edges.\nIn the case of the given path graph, count[c] is equal to the number of servers to the left of c multiplied by the servers to the right of c.\n
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Example 2:

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\nInput: edges = [[0,6,3],[6,5,3],[0,3,1],[3,2,7],[3,1,6],[3,4,2]], signalSpeed = 3\nOutput: [2,0,0,0,0,0,2]\nExplanation: Through server 0, there are 2 pairs of connectable servers: (4, 5) and (4, 6).\nThrough server 6, there are 2 pairs of connectable servers: (4, 5) and (0, 5).\nIt can be shown that no two servers are connectable through servers other than 0 and 6.\n
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Constraints:

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(listof exact-integer?))\n )", "__typename": "CodeSnippetNode" }, { "lang": "Erlang", "langSlug": "erlang", "code": "-spec count_pairs_of_connectable_servers(Edges :: [[integer()]], SignalSpeed :: integer()) -> [integer()].\ncount_pairs_of_connectable_servers(Edges, SignalSpeed) ->\n .", "__typename": "CodeSnippetNode" }, { "lang": "Elixir", "langSlug": "elixir", "code": "defmodule Solution do\n @spec count_pairs_of_connectable_servers(edges :: [[integer]], signal_speed :: integer) :: [integer]\n def count_pairs_of_connectable_servers(edges, signal_speed) do\n \n end\nend", "__typename": "CodeSnippetNode" } ], "stats": "{\"totalAccepted\": \"10.3K\", \"totalSubmission\": \"18K\", \"totalAcceptedRaw\": 10270, \"totalSubmissionRaw\": 17957, \"acRate\": \"57.2%\"}", "hints": [ "Take each node as the root of the tree, run DFS, and save for each node i, the number of nodes in the subtree rooted at i whose distance to the root is divisible by signalSpeed.", "If the root has m children named c1, c2, …, cm that respectively have num[c1], num[c2], …, num[cm] nodes in their subtrees whose distance is divisible by signalSpeed. Then, there are ((S - num[ci]) * num[ci]) / 2that are connectable through the root that we have fixed, where S is the sum of num[ci]." ], "solution": null, "status": null, "sampleTestCase": "[[0,1,1],[1,2,5],[2,3,13],[3,4,9],[4,5,2]]\n1", "metaData": "{\n \"name\": \"countPairsOfConnectableServers\",\n \"params\": [\n {\n \"name\": \"edges\",\n \"type\": \"integer[][]\"\n },\n {\n \"type\": \"integer\",\n \"name\": \"signalSpeed\"\n }\n ],\n \"return\": {\n \"type\": \"integer[]\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"

Compiled with clang 17 using the latest C++ 20 standard, and libstdc++ provided by GCC 11.

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 21. Using compile arguments: --enable-preview --release 21

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Most standard library headers are already included automatically for your convenience.

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Python 2.7.12.

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C# 12 with .NET 8 runtime

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Node.js 20.10.0.

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Ruby 3.2

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Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms

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Go 1.21

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Racket CS v8.11

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Using #lang racket

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Dart 3.2

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