YAPC::Russia::Golf 2008

YAPC::Russia::Golf is a contest for solving the task with shortest code, which happened during the conference YAPC::Russia «May Perl» 2008 on 17 and 18 May of 2008 in Moscow.

The winner is a person who writes a programme that contains minimal number of non-space symbols. It is possible to use any option of the perl interpreter (such as -l, -n, -p), but those symbols (together with hyphens) are added to the total number of symbols in the programme. Path to perl in a sheebang is not calculated, but the options (if they present there) are.

Task 1

It is easy to obtain with the help of regular expression that a number may be divided by 4:

#!perl
 while(<>) {
     if( /[02468][048]$/ || /[13579][26]$/ || /^[048]/ ) {
         print "yes\n";
     } else {
         print "no\n";
     }
 }

Try to write a code without arithmetic, bitwise or string operators and without the operator x (only control statements and regular expressions), the code must check whether the number may be divided by 11. STDIN gets natural numbers less than 10⁸⁰. For each number print yes if it is dividable, and no otherwise.

Task 2

First line of STDIN is a number N, others compose the block of equally long strings which consist of spaces and symbols #. String length and their number are both not more than 200.

Find the maximal number of # symbols that fit into any rectangle with the square exactly equal to N and such that each cell of it is situated within the given block.

Input example

Output example
14

Note. No rectangle 1 × 25 fits, we does not count them; rectangles 25 × 1 cover 13 cells maximum; and a rectangle 5 × 5 that covers 14 symbols is shown below: