func main[] : I64
    let answer: I64 = math.abs(os.urandom()) % 100

    while true
        io.println("Guess a number: ")
        let guess: I64 = io.read_stdin() |> str.trim() |> str.parse_i64()

        if guess == answer
            io.println("You win!")
            break
        else if guess < answer
            io.println("Too low!")
        else
            io.println("Too high!")