Verify my lasagne

Retina, 38 34 bytes

Thanks to Grimy for saving 4 bytes.

Have a regex with your lasagne.

Byte count assumes ISO 8859-1 encoding.

^([, ]+¶)?,{5,}(¶[@#]+¶[-~]*){2,}$

Assumes that the input ends with a trailing linefeed. Prints 1 (match) for valid lasagnes and 0 (no match) for invalid ones.

Try it online!


This is just a standard .NET regex matched against the input, except that Retina provides the alias for linefeeds or \n.

Since the input is guaranteed to be rectangular, we only need to check the width of the lasagne on one of the rows.

^           # Anchor the regex to the beginning of the input.
([, ]+¶)?   # Match an optional first line of only commas an spaces.
,{5,}       # Match at least 5 commas.
(           # Match this at least twice to ensure at least two layers of sauce.
  ¶[@#]+    #   Match a line of sauce.
  ¶[-~]*    #   Match a line of pasta. This line may be empty (which would
            #   indicate the end of the input.
$           # Make sure we've indeed reached the end. Note that `$` can
            # match either at the very end of the input, or in front of
            # the trailing linefeed.

Grime, 43 bytes

e`[ \,]+/?/(\,/[#@]^/[\-~]/+/[#@]/?)+{5-,4-

Try it online! Prints 1 for match and 0 for no match.


Grime is designed for matching two-dimensional patterns, which are constructed piece by piece from smaller patterns. I define the optional top layer first, then the other layers by repeating a vertical stripe.

e`                                           Match entire input against pattern:
        /?                                   Optionally
  [ \,]+                                     a row of spaces and commas,
          /                                  below that
           (                       )         this pattern
                                    +        repeated horizontally
                                     {5-,4-  having size at least 5x4. 
                                             The brace is closed implicitly.
                                             "This pattern" is a vertical stripe containing
            \,                               a comma,
              /                              below that
               [#@]^/[\-~]                   a sauce character on top of a noodle character
                                             (the ^/ is like / but with higher precedence)
                          /+                 repeated vertically,
                            /                below that
                                 /?          optionally
                             [#@]            a sauce character.