Problem: Missing Digit

Code: Missing+Digit/tails_1644381918

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)

/ (foldr) 
    @ (= fstLine) 
    477 (integer) <--arg( B A ) 
    - (subtract) <--arg( D C ) 
        @ (= C) 
        (implicit arg = D)