Minimum Island Approach

In this lesson, Alvin explores the strategy to solving the following interview problem:

Write a function, minimum_island, that takes in a grid containing Ws and Ls. W represents water and L represents land. The function should return the size of the smallest island. An island is a vertically or horizontally connected region of land.

You may assume that the grid contains at least one island.

grid = [
['W', 'L', 'W', 'W', 'W'],
['W', 'L', 'W', 'W', 'W'],
['W', 'W', 'W', 'L', 'W'],
['W', 'W', 'L', 'L', 'W'],
['L', 'W', 'W', 'L', 'L'],
['L', 'L', 'W', 'W', 'W'],
]

minimum_island(grid) # -> 2

grid = [
['L', 'W', 'W', 'L', 'W'],
['L', 'W', 'W', 'L', 'L'],
['W', 'L', 'W', 'L', 'W'],
['W', 'W', 'W', 'W', 'W'],
['W', 'W', 'L', 'L', 'L'],
]

minimum_island(grid) # -> 1

grid = [
['L', 'L', 'L'],
['L', 'L', 'L'],
['L', 'L', 'L'],
]

minimum_island(grid) # -> 9

If you need additional support taking these DSA skills and actually applying them, take Alvin's complete data structures and algorithms course on Structy. You can try out the concepts yourself in their interactive code editor and learn advanced DSA patterns like stack exhaustive recursion.

Use this link to get 20% off the entire Structy DSA learning experience.

Follow Alvin on LinkedIn: https://www.linkedin.com/in/alvin-zablan-b73a92117/