## January 18, 2009

### A New Puzzle for the Year?

I am always looking for new puzzles to try out. Last semester I finished a book of Hidato puzzles. This semester I bought a book of Kenken puzzles of which I will write after I have solved a few more of the harder ones.

So far, that book is not so challenging. But a new type of "puzzle" has caught my eye. It's not a traditional puzzle because it is actually a board game. What is interesting about this board game is that they actually sell "puzzle" books with hundreds of game problems to solve.

The game I am talking about is called Go. It is a popular game in Asian countries, although it is played worldwide nowadays. It is also one of the few very popular board games remaining where a computer still can't beat the best human players.

The fact that they sell "puzzle" books about this game made it even more appealing for me. I am currently learning the rules and some simple strategy. My next step will be to buy a Go problem book. I will write more about it as I learn. Maybe I'll even explain some of the rules later on. I can't wait to try some Go puzzles!

## October 4, 2008

### A New Puzzle For This Semester: Hidato!

I am fond of puzzles. I enjoy having something fun and entertaining to do during boring clas... during my free time. I even had a week about some of my favorites here in this blog.

So, as a puzzle enthusiast, it is my duty to let all of you know when I discover a new puzzle to waste my neurons on. Here is my short review of Hidato (based on the puzzle book I own, by Dr. Gyora Benedek):

Concept:
Complete the sequence of numbers, which must be adjacent either horizontally, vertically or diagonally.
Difficulty: C
The puzzles don't really seem to get much harder as you progress in difficulty. And there is a small number of tactics to learn (as opposed to Sudoku and Kakuro, which have tons of tactics). The puzzles remain somewhat easy and only get bigger as the "difficulty" goes up.
Entertainment Value: B
It's fun to follow the sequence around.
Benefit: C
If you're learning how to count from one to one hundred, then this is the puzzle for you. Otherwise, your mind won't really gain much from it.
Replay Value: A
The fact that it doesn't take too much time too solve makes you feel like you need to solve many more to feel satisfied. I usually solve about five in a row.
Overall:B
Fun, but not challenging enough for those who have done a lot of Kakuro and Sudoku.

## February 7, 2008

### Puzzle Week, Day 7: Kakuro

I saved my favorite puzzle for last. Kakuro is said to be a mix of Sudoku and Crossword puzzles. It has logic similar to Sudoku, but with math added to it. The idea is to fill rows and columns with the specified sums using the numbers from 1 to 9 and without repeating a number in that column or row. A sample Kakuro puzzle and solution are below:

I find Kakuro puzzles challenging, but very fun. They really help you work on your math. That is, unless you use combinations cheat sheets, which really take the fun out of it and makes it loose its purpose. First time I tried Kakuro, it took me about 45 minutes to finish an easy one. After a while, I managed to get the time down for easy ones to around 5 minutes. Now I am back to about an hour of solving time tackling a book called "Black Belt Kakuro", which is the hardest out of a series of four Kakuro books. My challenge is trying to solve them without annotating possibilities in the cells, that is, only writing in a cell when I have the answer. Kakuro really is a great puzzle. If there is one puzzle book that you buy in the whole year, be sure to make it Kakuro. Happy solving!

## February 6, 2008

### Puzzle Week, Day 6: Crossword Puzzles

In my opinion, crossword puzzles are the most challenging puzzles of all. No amount of logic alone will get you through them. My wife and I started trying to solve crossword puzzles together about two months ago, mainly as a way to work on our English. The newspaper crossword puzzles proved to be too difficult for us, so we ended up buying a book of "over-easy" crossword puzzles. We still have trouble solving them, but once in a while we manage a perfect solution.

The compelling aspect of crossword puzzles is their need for mastery of the language and knowledge of the world. You can really learn a lot by solving (or trying to solve) crossword puzzles. You get to work on your geography, trivia, and language, all while having fun. Of course, if you start with newspaper puzzles, you will definitely feel overwhelmed.

I actually tried to work on one in my native language (Spanish), but did even worse. I think I'll stick with over-easy English crossword puzzles for now.

## February 5, 2008

### Puzzle Week, Day 5: Masyu

I am sure most of you have not heard of Masyu. I encountered this puzzle when I purchased (or received as a gift) a book called something like "The Monster Book of Japanese Puzzles". Masyu became one of my favorites. It's not too difficult in my opinion, but very fun. The idea is that you have black and white circles in a grid. You have to draw one continuous line that goes through all the circles. Lines cannot pass over one grid cell more than once. Lines must also turn 90 degrees when encountering a black circle. When encountering a white circle, lines cannot turn on the circle, but must turn before or after (or both). That is all there is to it. A sample puzzle with solution looks like this:

Interestingly, the name Masyu means "evil influence". That is not the original name though. The original name was actually Shiroshinju Kuroshinju, which means "white pearls and black pearls" in Japanese. Some of the characters were misread by the preseident of Nikoli, the company who publishes these puzzles, and the name became Masyu. Personally I prefer the short and simple Masyu.

Masyu books are not very common, but I have seen them in stores, as individual books and as part of puzzle collections. If you are really eager to try Masyu and can't find it, you can check the Nikoli website and order a book directly from Japan. Enjoy!

## February 4, 2008

### Puzzle Week, Day 4: Hanjie

Also known as Nonograms, Hanjie is a picture and number puzzle. The object is to fill in the cells in a grid to form a picture. To know which cells to fill in, you are given a set of numbers for each row and column that let you know how many consecutive cells are filled and in what order. For example, a "10 3" would mean that you have ten consecutive cells followed by an arbitrary numbers of empty cells and again followed by three consecutive filled cells. An example of a puzzle being solved (taken from Wikipedia) is shown below:

Although the more advanced Hanjie puzzles may still not be as challenging as advanced Sudoku puzzles, they are yet another good way to work on recognizing patterns. There is also some simple math (mostly counting) involved. I find Hanjie puzzles to be good for when I don't want to strain my mind as much but still want to work on puzzles. A good book to start out with if you are interested in Hanjie puzzles is "The Essential Book of Hanjie and How to Solve It", by Gareth Moore. Also, if you have a Nintendo DS, you might want to check out Picross, which is yet another name for Hanjie puzzles.

## February 3, 2008

### Puzzle Week, Day 3: Tangrams

The rules for tangram puzzles are very simple. You are given a shadow and seven pieces. The goal is to form the shadow's shape using the whole set of pieces. The pieces look like this:

And the shapes you have to build look like this:

Like jigsaw puzzles, tangrams help a lot with pattern recognition. Plus, they are very fun to play against friends, trying to see who can solve them first. They usually don't take too long, so if you want just a quick, short challenge, be sure to check tangrams out!

## February 2, 2008

### Puzzle Week, Day 2: Jigsaw Puzzles

The Spanish word for jigsaw puzzles is "rompecabezas". This literally means "head breaker". And it is no wonder why they got that name. Although many of use grew up with jigsaw puzzles, most of these had a lot less than 100 pieces. But when tackling a real jigsaw puzzle (one with 1,000 pieces or more), that's when you really start to feel your head about to brake. Of course, for serious jigsaw puzzle fans, 1,000 pieces is a walk in the park. The largest jigsaw puzzle has about 24,000 pieces. I actually saw it at a game store and I think I could fit in its box!

Jigsaw puzzles are a great way to work on your pattern recognition skills. You develop the ability to better recognize edges, color contrasts, and shapes. I recently started solving jigsaw puzzles and have already completed two 1000-piece jigsaw puzzles, the second one together with my wife (yes, jigsaw puzzles are very fun for building with friends!). If you think jigsaw puzzles are lame and 24,000 pieces are not enough for you, you can always try a colorless jigsaw puzzle. Go for it!

## January 31, 2008

### It's Puzzle Week! And Starting Off is Sudoku!

I am a big fan of puzzles. I love giving my brain a good workout. If you are ever in the mood to do so too, just grab any of the puzzles I will be presenting this week and give them a try. I have selected my seven favorite puzzles which don't require a computer to play (although they should all be available on computer anyway).

I'll start with the very popular Sudoku. Although sometimes regarded to as a math puzzle, Sudoku is actually a logic puzzle. You could actually play Sudoku with any other set of symbols or even colors. Of course, numbers make it easier to solve since they can be easily verified by counting them. The object of the game is simple. Every row, every column, and every 3X3 grid must contain the numbers from 1 through 9 (without repeating!). Here is a sample unsolved grid:

Sudoku really helps with visualization. After some time of solving Sudoku puzzles, you will be able to cross out rows and columns by just looking briefly at the grid. The harder ones require you to cross out many rows at once and the evil ones are basically impossible to do without writing in all the possibilities for each cell. I personally prefer to solve Sudoku puzzles on paper, since I can handle the subscripts with much more ease.

Sudoku puzzles are a great place to start if you're interested in puzzles. They may get repetitive after a while, but even then, there are dozens of variants (like Jigsaw Sudokus and 16X16 Sudokus) to keep you busy.