the project is in japanese and i'm not fluent so it's probably not spot-on what you would actually say but here's how you use it: press space and enter starting digit(up to 83), then enter ending digit. the next thing it says is "next number?" and you're supposed to put in the next digit. this will repeat until you have done the number of digits you inputted earlier. the "." counts as a digit. if you get one wrong, it says "ah, it's not (your answer). it's (the next digit)." if you get all the way through, it says "Congratulations! You know pi to (digits) digits! You took (timer) seconds!"
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