Source: 1. Internet newsgroup rec.puzzles, 2. Richard Brabant, CSU Sacramento
_________________ | ___| | ___| | | ___| | ___________ | |________ | |___________| | ___| | | ___| | |___| | |_______________| | --> | _____________________ | ___| | | ___| | | ___|_______ | | |___________| | | ___| | | ___| | |___|_______________| |
|<------------ 15 ----------->| _______________________________ _ | 2 | | ^ |_______________| 3 | | |_______4_______|________ | | | | | 7 | | | | | | | | | |_____|__v_______ | | | | | | | | | 1 | | | | | 2 | |________ | | | 3 | | | | | | | |_____________|__ |_____________________________|___|______4________|Are there others?