Problem: 81 digit number

Code: 81+digit+number/tails_1701234364

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)

+ (concat) 
    : (append) 
        ; (save) -->let( B ) 
            `\ (special scans) 
                >> (tail) 
                    | (filter) 
                        @ (= fstLine) 
                        \ (char class) <--arg( A ) 
                            $ (= A) 
                            d (isDigit) 
                : (foldop: cons) 
        >> (tail) 
            \ (reverse) 
                (implicit arg = B)