Out of Memory! Hackerrank Medium: Queen's Attack II Python

Learn Python for free at Productive Dev: courses.productivedev.com Here I try a Medium Hackerrank algorithm problem called Queen's Attack II. The first solution uses unnecessary space and results in an out of memory error. It turns out that O(n^2) space is a problem! The second solution runs in O(k) time and O(1) space where k is the number of obstacles.