gawk: Signature Program

 
 11.3.11 And Now for Something Completely Different
 --------------------------------------------------
 
 The following program was written by Davide Brini and is published on
 his website (http://backreference.org/2011/02/03/obfuscated-awk/).  It
 serves as his signature in the Usenet group 'comp.lang.awk'.  He
 supplies the following copyright terms:
 
      Copyright (C) 2008 Davide Brini
 
      Copying and distribution of the code published in this page, with
      or without modification, are permitted in any medium without
      royalty provided the copyright notice and this notice are
      preserved.
 
    Here is the program:
 
      awk 'BEGIN{O="~"~"~";o="=="=="==";o+=+o;x=O""O;while(X++<=x+o+o)c=c"%c";
      printf c,(x-O)*(x-O),x*(x-o)-o,x*(x-O)+x-O-o,+x*(x-O)-x+o,X*(o*o+O)+x-O,
      X*(X-x)-o*o,(x+X)*o*o+o,x*(X-x)-O-O,x-O+(O+o+X+x)*(o+O),X*X-X*(x-O)-x+O,
      O+X*(o*(o+O)+O),+x+O+X*o,x*(x-o),(o+X+x)*o*o-(x-O-O),O+(X-x)*(X+O),x-O}'
 
    We leave it to you to determine what the program does.  (If you are
 truly desperate to understand it, see Chris Johansen's explanation,
 which is embedded in the Texinfo source file for this Info file.)