The 9 Dots Puzzle
Connect all the dots using only 4 straight lines;
without lifting the pencil.
Each line can be as long or as short
as you like; and a dot may be crossed more than once.
Click anywhere to set endpoint of the lines.
This is an implementation of a popular classic puzzle.
(I don't know who invented it, if you do, please e-mail me).
CGI/PHP Programing by F. Permadi