Cracker Barrel Triangle Puzzle

Solving the puzzle

This site

Puzzle Home
Other size triangles

Triangle puzzle links

Dan O'Brien puzzle page
UVA Class assignment
The Cracker Barrel Page

Other Links

Baseball Schedule Tools
Running / Biking pace chart

Years ago while waiting to eat at a Cracker Barrel restaurant I tried to solve the above puzzle with little success. After many failures the thought occurred that a solution could be found via a program. My original effort goes back to about 1974 with a Fortran program on an old IBM 1130. If I remember right the program took 24 hours to run. I was amazed by the number of solutions and could not understand why it was so difficult to do manually.

Years later, somewhere in the late 90s the program was rewritten in Progress, a nice 4GL for accessing a Progress DB but not to swift with calculations. This ran for about an hour on a HP9000 Unix box. It was then rewritten in C on the same machine, my one and only C program and was amazed to find it ran in a few seconds. All of the above efforts was done only with the case where the program assumed the top hole was empty.

After the company I worked for went bankrupt, the Unix box disappeared and the program went with it so I decided to write it from memory in Visual Basic. This time the problem was solved for all four non-redundant cases. It ran on a 1GHz Windows PC and finished in approximately 3 minutes. I then checked the web to see if there was any sites that published a solution and found several. These links can be found under the triangle puzzle links in the left-hand navigation areas. My favorite is Dan O'Briens puzzle page which has a much more extensive analysis than this site.

My solutions were then stored in an Access database and a couple of ASP pages were written to display up to 100 solutions at a time depending on the parameters selected by the user. Each solution has a link that will display that single solution in detail.