gawk: Signature Program

1 
1 11.3.11 And Now for Something Completely Different
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1 
1 The following program was written by Davide Brini and is published on
1 his website (http://backreference.org/2011/02/03/obfuscated-awk/).  It
1 serves as his signature in the Usenet group 'comp.lang.awk'.  He
1 supplies the following copyright terms:
1 
1      Copyright (C) 2008 Davide Brini
1 
1      Copying and distribution of the code published in this page, with
1      or without modification, are permitted in any medium without
1      royalty provided the copyright notice and this notice are
1      preserved.
1 
1    Here is the program:
1 
1      awk 'BEGIN{O="~"~"~";o="=="=="==";o+=+o;x=O""O;while(X++<=x+o+o)c=c"%c";
1      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,
1      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,
1      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}'
1 
1    We leave it to you to determine what the program does.  (If you are
1 truly desperate to understand it, see Chris Johansen's explanation,
1 which is embedded in the Texinfo source file for this Info file.)
1