## Welcome to Bob’s Mad Veterinarian Puzzle Page

In September of 1998, after fiddling with this puzzle format for about a
decade, I posted the first
‘Mad Veterinarian’
puzzle to the rec.puzzles
newsgroup:
A mad veterinarian has created three animal transmogrifying machines.

Place a cat in the input bin of the first machine, press the button, and
… whirrr … bing! Open the output bins to find two dogs and five mice.

The second machine can convert a dog into three cats and three mice, and
the third machine can convert a mouse into a cat and a dog. Each machine can
also operate in reverse (e.g. if you've got two dogs and five mice, you can
convert them into a cat).

You have one cat.
- Can you convert it into seven mice?
- Can you convert it into a pack of dogs, with no mice or cats left over?

Puzzle solvers discovered that it was impossible to convert a single cat into
seven mice, nor to a lonesome pack of dogs. However, they posed and answered
followup questions, such as *“how many mice ***can** be created from a
single cat” and *“what’s the smallest number of cats that can
be turned into just dogs”*.

Below, I’ve set up several puzzles of this type, and a java applet
that lets you solve them. Each applet deals with one set of machines and poses
several conversions for you to try to solve.

How To Solve Mad Veterinarian Puzzles

Easy Three Animal Labratory
Mar/17/2003

Original Three Animal Labratory
Mar/17/2003

Hard Four Animal Labratory
Mar/17/2003

Harder Four Animal Labratory
Apr/1/2003

Schoolhouse Jelly Beans
Apr/2/2003