I knew the answers to all of these questions two years ago when I had just graduated, but I've completely forgotten what heapsort is (despite having used it a few times in programming contests) and cannot offhand remember what "bipartite" means (googled, saw the wikipedia image and instantly remembered maxflow and Ford–Fulkerson although I guess a DFS is good enough to determine bipartite-ness).

Why is the ability to retain this information at the top of my mind at all times necessary for me to be a Software Developer?