# Chocolate Milk Puzzle

September 7th, 2007 by Multimedia Mike

So I had a little carton of chocolate milk with my lunch today (longtime readers have guessed that I must still be in elementary school). On one side of the carton was a word search puzzle that challenged me to find 6 words hidden in the jumble of letters. It occurred to me that this represented an allegory for reverse engineering.

I generally liken RE to an extraordinarily complex, or just tedious, puzzle. This is a more straightforward puzzle.

Task: Find 6 strings of characters. What strings? I wasn’t sure exactly. Lesser word searches explicitly tell you which words to find. Those puzzles can be solved via a brute force algorithm that most of us figure out by the age of 5. I knew that these had to be coherent English words. Eventually, I re-read the instructions and noticed that the words were supposed to pertain to “foods made from grain”. Lesson: Gather all the intelligence you can before delving into the meat of the puzzle.

Next, there is domain knowledge. I have done a few word search puzzles before and so I know that I am supposed to look for strings of characters running left -> right, right -> left, top -> bottom, bottom -> top, and also diagonally. And I have some clue about foods made from grain. So I am off.

Then, I started theorizing about how the original puzzler (or whatever you call a person who develops puzzles) must have put this puzzle together. Since there are 6 words, I hypothesized that 2 would be horizontal (one for each direction), 2 would be vertical (again, one for each direction), and 2 would be diagonal. This would make good use of the parameters of a stock word search. I refined my initial search using these assumptions.

I was correct about the 2 horizontal and 2 vertical. I also found one more horizontal word. I methodically scanned every diagonal possibility, much to the disdain of my overworked eyes. I could not find any word on that orientation. So I revised my original assumption and assumed the remaining word must also be horizontal.

Finally, there’s the matter of validation: determining if one’s RE results are correct. Unlike binary RE, this puzzle makes it easy. So I check and… I don’t believe it! I only got 4 of them correct. I got another partially correct. And yeah, I didn’t think ‘bean’ was a valid grain.

Posted in Reverse Engineering | 3 Comments »

## 3 Responses

1. Kostya Says:

I remember some Sierra games that wold generate such puzzle for you with either fixed set of words (Castle of Doctor Brain) or different words (in one of three languages, Island of Doctor Brain).

Trained on them this one is easy. Spoilers: there is one left-right word that polly wants, one right-left word on which CPUs are made, one top-bottom for horses, and three bottom-top words in last four columns.

2. Robert Swain Says:

Has anyone else noticed that the problem statement mentions that there are 6 answers and on the answer page there are 7. I found ‘6’ (cake instead of pancake, meal instead of oatmeal… but then we call it porridge here I believe).

3. Multimedia Mike Says:

Yeah, I noticed the seven answers as well. And I also found cake instead of pancake (I counted that as partial), which I believe is equally valid since flour is the principle ingredient of cake.

I always wondered what porridge was. Indeed, these milk carton puzzles are a tad Ameri-centric.