#185 Counting the Number of Islands

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Wildberries X5

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AlgorithmsArraysPractice

There is an n by m matrix. 1 represents land, and 0 represents water. Count the number of islands. An island is an arbitrary piece of land that is not connected to other land areas. Diagonal connections do not count. Everything outside the matrix is water.

Example 1:

Input: grid = [
    ["1", "1", "1", "1", "0"],
    ["1", "1", "0", "1", "0"],
    ["1", "1", "0", "0", "0"],
    ["0", "0", "0", "0", "0"]
]

Output: 1

Example 2:

Input: grid = [
    ["1", "1", "0", "0", "0"],
    ["1", "1", "0", "0", "0"],
    ["0", "0", "1", "0", "0"],
    ["0", "0", "0", "1", "1"]
]

Output: 3

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