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The question asked was to find the Number of islands in a grid ( . I solved this with a reasonable amount of time left, which was then followed up with a few interesting question as follows -

Q.) What if the island could extend to a distance of K units including water (0) as a part of it ? How would this impact the functions and base condition of recursion?
Q.) What would be the time complexity in above case ?
Q.) Can we use parllelization/ multi threading to solve this problem ?
Q) If multiple threads are used in the below example, how would you determine which thread to terminate ?