Whenever you're waiting in a Queue, you can think about Stacks to pass the time. Particularly what it would be like to take the bottom can from a stacked display. O(1) to take, but O(omg) to clean up. ;_;
Anyway, learn about stacks in this video!
Some other links:
http://www.ardendertat.com/2011/11/08/programming-interview-questions-14-check-balanced-parentheses/
http://clarkfeusier.com/2015/01/16/interview-question-balanced-parentheses-stack.html
https://www.interviewcake.com/question/java/matching-parens
See you next time!
Music: Antonio Vivaldi - Concerto in C major Op.8 No.12, European Archive, https://musopen.org/music/3087/antonio-vivaldi/concerto-in-c-major-op8-no12/
Some images: http://www.snappygoat.com
