{ "data": { "question": { "questionId": "1527", "questionFrontendId": "1411", "boundTopicId": null, "title": "Number of Ways to Paint N × 3 Grid", "titleSlug": "number-of-ways-to-paint-n-3-grid", "content": "

You have a grid of size n x 3 and you want to paint each cell of the grid with exactly one of the three colors: Red, Yellow, or Green while making sure that no two adjacent cells have the same color (i.e., no two cells that share vertical or horizontal sides have the same color).

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Given n the number of rows of the grid, return the number of ways you can paint this grid. As the answer may grow large, the answer must be computed modulo 109 + 7.

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Example 1:

\n\"\"\n
\nInput: n = 1\nOutput: 12\nExplanation: There are 12 possible way to paint the grid as shown.\n
\n\n

Example 2:

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\nInput: n = 5000\nOutput: 30228214\n
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\n

Constraints:

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

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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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Python 2.7.12.

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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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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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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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Python 3.10.

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Rust 1.58.1

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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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Dart 2.17.3

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