{ "data": { "question": { "questionId": "3232", "questionFrontendId": "2941", "boundTopicId": null, "title": "Maximum GCD-Sum of a Subarray", "titleSlug": "maximum-gcd-sum-of-a-subarray", "content": null, "translatedTitle": null, "translatedContent": null, "isPaidOnly": true, "difficulty": "Hard", "likes": 10, "dislikes": 0, "isLiked": null, "similarQuestions": "[]", "exampleTestcases": "[2,1,4,4,4,2]\n2\n[7,3,9,4]\n1", "categoryTitle": "Algorithms", "contributors": [], "topicTags": [ { "name": "Array", "slug": "array", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Math", "slug": "math", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Binary Search", "slug": "binary-search", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Number Theory", "slug": "number-theory", "translatedName": null, "__typename": "TopicTagNode" } ], "companyTagStats": null, "codeSnippets": null, "stats": "{\"totalAccepted\": \"240\", \"totalSubmission\": \"472\", \"totalAcceptedRaw\": 240, \"totalSubmissionRaw\": 472, \"acRate\": \"50.8%\"}", "hints": [ "Try to answer the query of asking GCD of a subarray in O(1) using sparse tables and preprocessing.", "For every index L, let’s find the subarray starting at the index L and maximizing gcd-sum.", "Use the fact that if L is fixed, then by adding one more element to the end of a subarray, two things can happen: the gcd remains the same as the last gcd or becomes at least half of the last one.", "Now we can use binary search to find the last index R such that gcd of the elements of nums[L..R] would be equal to nums[L].", "Now add nums[R + 1] to the current subarray and continue the process to find the last index that has the same gcd as the current gcd of elements." ], "solution": null, "status": null, "sampleTestCase": "[2,1,4,4,4,2]\n2", "metaData": "{\n \"name\": \"maxGcdSum\",\n \"params\": [\n {\n \"name\": \"nums\",\n \"type\": \"integer[]\"\n },\n {\n \"type\": \"integer\",\n \"name\": \"k\"\n }\n ],\n \"return\": {\n \"type\": \"long\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"

Compiled with clang 11 using the latest C++ 20 standard.

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Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

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

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OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

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

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Includes Pair class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.

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Python 2.7.12.

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Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.

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For Map/TreeMap data structure, you may use sortedcontainers library.

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Note that Python 2.7 will not be maintained past 2020. For the latest Python, please choose Python3 instead.

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Compiled with gcc 8.2 using the gnu11 standard.

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Your code is compiled with level one optimization (-O1). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.

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

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For hash table operations, you may use uthash. \\\"uthash.h\\\" is included by default. Below are some examples:

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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Your code is run with --harmony flag, enabling new ES6 features.

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lodash.js library is included by default.

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For Priority Queue / Queue data structures, you may use 5.3.0 version of datastructures-js/priority-queue and 4.2.1 version of datastructures-js/queue.

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Ruby 3.1

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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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Swift 5.5.2.

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Go 1.21

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Support https://godoc.org/github.com/emirpasic/gods@v1.18.1 library.

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Python 3.10.

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Scala 2.13.7.

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Kotlin 1.9.0.

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Rust 1.58.1

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Supports rand v0.6\\u00a0from crates.io

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PHP 8.1.

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With bcmath module

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TypeScript 5.1.6, Node.js 16.13.2.

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lodash.js library is included by default.

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Run with Racket 8.3.

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Dart 2.17.3

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Your code will be run directly without compiling

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