# code: http://golf.shinh.org/reveal.rb?Looped+grid/tails_1644978021&nbb
# target Nibbles version: 0.23
# commenter version: 0.1.2.181

#(implicit map with implicit range):[[int]] 
    fstInt #($):int 
    \B A 
    . #(map):[int] 
        , #(range from 1):[int] 
            fstInt #(_):int 
        \C 
        + #(add):int 
            != #(abs diff):int 
                C #($):int 
                B #(@):int 
            ~ #(auto = 1):auto