lines
m:
    pop-a
    4
    8
    crange
        double
        binary #(num to list)
            double
            dec
        m2
    m4
        push-a
        read-nums
            *
        z1
        sum
        not
    f6
    head
    tail
    init
        44
        swap
        -
    m3
    show-line
    push-a
    "?"
    split
    zip