a fun exercise is to write this in Dafny https://github.com/dafny-lang/dafny https://github.com/dafny-lang/dafny It's simple enough to be attempted with a limi

a fun exercise is to write this in Dafny https://github.com/dafny-lang/dafny https://github.com/dafny-lang/dafny It's simple enough to be attempted with a limited knowledge of Dafny, but subtle enough that you will need to think about what you are doing https://www.youtube.com/watch?v=-_tx3lk7yn4 https://www.youtube.com/watch?v=-_tx3lk7yn4