[2015-10-23] Challenge #237 [Hard] Takuzu Solver : dailyprogrammer
Takuzu is a simple and fairly unknown logic game similar to Sudoku. The objective is to fill a square grid with either a "1" or a "0". There are a couple of rules you must follow:

You can't put more than two identical numbers next to each other in a line (i.e. you can't have a "111" or "000").
The number of 1s and 0s on each row and column must match.
You can't have two identical rows or columns.

To get a better hang of the rules you can play an online version of this game (which inspired this challenge) here.

Input Description

You'll be given a square grid representing the game board. Some cells have already been filled; the remaining ones are represented by a dot. Example:

....  0.0.  ..0.  ...1

Output Description

Your program should display the filled game board. Example:

1010  0101  1100  0011

Inputs used here (and available at the online version of the game) have only one solution. For extra challenge, you can make your program output all possible solutions, if there are more of them.

http://code.activestate.com/recipes/578414-takuzu-solver/
http://blog.jverkamp.com/2015/10/29/takuzu-solver/
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