Any one else hooked on Sudoku ?

[Jangar]

Wow! Mind boggling!! Did you know they've played it since 1989!

http://www.tocatch.info/en/Hashiwokakero...on_methods

Actually it goes back longer than that...

I call them euler puzzles after the man who devised the method of knowing if they are possible or not. Leonhard Euler was a brilliant 18th century mathematician who solved the puzzle of the Konigsberg bridges (now Kaliningrad, in Russia). Seven bridges connected both sides of the city and two islands in between. The townsfolk passed their time for many years trying (unsucessfully) to find a route which would cross each bridge only once. Euler proved that is was not possible, until an eighth bridge was constructed (unfortunately litte remains of the original city or its bridges since the 2nd world war). Nevertheless Euler's Rule survives, and is now used in planning routes and service territories (for postal services, meter reading, door-to-door deliveries, etc) the world over, to eliminate unnecessary travel and back-tracking.