{ "data": { "question": { "questionId": "3463", "questionFrontendId": "3206", "boundTopicId": null, "title": "Alternating Groups I", "titleSlug": "alternating-groups-i", "content": "

There is a circle of red and blue tiles. You are given an array of integers colors. The color of tile i is represented by colors[i]:

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Every 3 contiguous tiles in the circle with alternating colors (the middle tile has a different color from its left and right tiles) is called an alternating group.

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Return the number of alternating groups.

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Note that since colors represents a circle, the first and the last tiles are considered to be next to each other.

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Example 1:

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Input: colors = [1,1,1]

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Output: 0

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Explanation:

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\"\"

\n
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Example 2:

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Input: colors = [0,1,0,0,1]

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Output: 3

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Explanation:

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\"\"

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Alternating groups:

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\"\"\"\"\"\"

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Constraints:

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Compiled with clang 17 using the latest C++ 23 standard, and libstdc++ provided by GCC 13.

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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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lodash.js library is included by default.

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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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Swift 5.9.

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You may use swift-algorithms 1.2.0 and swift-collections 1.1.0.

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Go 1.21

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Python 3.11.

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Scala 3.3.1.

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Kotlin 1.9.0.

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PHP 8.2.

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TypeScript 5.1.6, Node.js 20.10.0.

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Racket CS v8.11

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Required data/gvector data/queue data/order data/heap automatically for your convenience

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Dart 3.2. You may use package collection

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