# code: http://golf.shinh.org/reveal.rb?checkers+pattern/tails_1642067881&nbb
# target Nibbles version: 0.21
# commenter version: 0.1.2.181

#(implicit map with implicit range):[[int]] 
    fstInt #($):int 
    \B A 
    . #(map):[int] 
        + #(add):[int] 
            B #($):int 
            `, #(range from 0):[int] 
                sndInt #(;_):int 
        \C 
        % #(modulus):int 
            C #($):int 
            ~ #(auto = 2):auto