LeetCode 200: Number of Islands

I had to watch some YouTube videos for the solution to this problem. I am not sure if this is the best solution though, one day I will revisit it.

LeetCode #73: Set Matrix Zeroes

Here is my solution to Set Matrix Zeros problem in PHP: Results Runtime: 52 ms, faster than 13.33% of PHP online submissions for Set Matrix Zeroes. Memory Usage: 19.8 MB, less than 80.00% of PHP online submissions for Set Matrix Zeroes.