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Grokking the Coding Interview Patterns in Go

Solution: Island Perimeter

Understand how to compute the perimeter of an island in a grid by iterating through cells and adjusting for shared edges. Learn an efficient matrix-based solution with O(row × col) time complexity and constant space use.

We'll cover the following...

Statement

You are given a grid with dimensions row x col, where each cell represents either land (grid[i][j] = 1) or water (grid[i][j] = 0). The grid satisfies the following conditions:

  • Cells are connected only horizontally or vertically (not diagonally).

  • The grid is surrounded by water and contains exactly one island, consisting of one or more connected land cells.

  • The island has no lakes, meaning no water is enclosed within the island that connects to the surrounding water. ...