This reminds me of when I learned to program on my casio calculator. There was a function to detect a key press which would return a number identifying the pre

This reminds me of when I learned to program on my casio calculator. There was a function to detect a key press which would return a number identifying the pressed key. I needed to map that number to the letter printed on the key to print it on the screen. I don't remember whether there was no hashmap data structure or I just didn't know about it, but I implemented it with a serie of if. The problem with that solution is that while mapping A was fast, Z was very slow because it was at the end of the list. That is how I discovered divide and conquer/ dichotomy with if branches.