Problem: i wrote this on my phone at the airport

Code: i+wrote+this+on+my+phone+at+the+airport/tails_1692193487

Nibbles version: 0.2 | 0.21 | 0.22 | 0.23 | 0.24 | 0.25 | 1.00

Format: Compact | Simple | +Type | Table | JSON | .nbl (DeBruijn) | .nbl (names)

(implicit map with implicit range) 
    + (add) 
        `$ (signum) 
            - (subtract) 
                ~ (auto = 1) 
                / (divide) 
                    30 (integer) 
                    r (read str at base) 
                        @ (= fstLine) 
                        2 (integer) 
        % (modulus) 
            / (foldr1) 
                @ (= fstLine) 
                $ (= B) <--arg( B A ) 
            4 (integer) 
    ~ (tuple) <--arg( D C ) 
        (implicit arg = D) 
        (implicit arg = D)