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2. Binary Search Letter Selection
Inspired by the commonplace algorithm, this design would be a binary or tertiary search on the next desired letter. Below are three potential visualizations of this, where a user would use the left or right arrow keys to narrow in on the desired letter. All three diagrams show the same progression of selection an “N”.
Binary Search Letter Selection 1
Initially Billy is given two options "A-M" or "N-Z". By hitting the "right arrow", two nodes appear under "N-Z" further dividing the letters into "N-T" or "U-Z". This could continue until Billy ends up at only one letter, which would require 4-5 key presses. The design shown above narrows down to three letter, at which point Billy could use the "left", "right", "select" keys to choose from one of three possible letters.
Binary Search Letter Selection 2