Had my phone screen last week.

Basically a variation of https://leetcode.com/problems/number-of-islands/

Instead of finding # of islands, the problem was to find the largest island in m x n grid

[1, 1, 1, 1, 0, 0]
[1, 1, 1, 1, 0, 0]
[1, 1, 1, 1, 0, 0]
[1, 1, 1, 1, 0, 1]

The largest island here would be 4x4 = 16 cells, and the interviewer just wanted me return the total cells of the largest island.

Basically did a BFS search of each neighboring cell, checking if it's an island and keeping a counter after each iteration of BFS, summing up the total.

Eventually coded the solution after some hints and bug fixes and the interviewer was satisfied.

update 03/29: Through to onsite