{ "data": { "question": { "questionId": "419", "questionFrontendId": "419", "boundTopicId": null, "title": "Battleships in a Board", "titleSlug": "battleships-in-a-board", "content": "

Given an m x n matrix board where each cell is a battleship 'X' or empty '.', return the number of the battleships on board.

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Battleships can only be placed horizontally or vertically on board. In other words, they can only be made of the shape 1 x k (1 row, k columns) or k x 1 (k rows, 1 column), where k can be of any size. At least one horizontal or vertical cell separates between two battleships (i.e., there are no adjacent battleships).

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Example 1:

\n\"\"\n
\nInput: board = [["X",".",".","X"],[".",".",".","X"],[".",".",".","X"]]\nOutput: 2\n
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Example 2:

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\nInput: board = [["."]]\nOutput: 0\n
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Constraints:

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Follow up: Could you do it in one-pass, using only O(1) extra memory and without modifying the values board?

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Compiled with clang 11 using the latest C++ 17 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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C# 10 with .NET 6 runtime

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Your code is compiled with debug flag enabled (/debug).

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Ruby 3.1

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Swift 5.5.2.

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Go 1.17.6.

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Python 3.10.

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