Stack on Rik Kisnah - Bloghttps://www.rik-kisnah.ai/tags/stack/Recent content in Stack on Rik Kisnah - BlogHugoenTue, 21 Apr 2020 09:00:00 -0700Min Stackhttps://www.rik-kisnah.ai/teach/coding/min-stack/Tue, 21 Apr 2020 09:00:00 -0700https://www.rik-kisnah.ai/teach/coding/min-stack/A stack that can tell you its smallest element instantly, at any moment. The answer is a second stack that remembers the smallest so far. Pay a little memory on every push to make one question free.Stackshttps://www.rik-kisnah.ai/teach/coding/stacks/Tue, 21 Feb 2017 09:00:00 -0800https://www.rik-kisnah.ai/teach/coding/stacks/A pile of plates. You only ever touch the top one. That is enough to match brackets, undo edits, unwind nested things, and find the next bigger number for every item in one pass. Learn the three shapes and you have the whole family.