Hexadoku solver

Hexadoku is the sudoku variant of the Elektor magazine. It uses a 16x16 grid with hexadecimal digits. They publish one grid in each monthly issue.
If you want to compete for one of their prizes but are too lazy or short of time for a brain and pencil solution, this solver is for you. It finds the solution in milliseconds on a Windows PC.
The only thing you have to do is to create a text file containing a copy of the grid in an appropriate format. For example, using the grid published in issue 437, november 2014, you create a file with the name 201411.txt (or whatever name you choose) with the following contents :

Hexadoku n°437 nov 2014

#6.24..3..e..70.a
#...7........1...
#1.3.0.4..2.8.c.e
#bd..c8....4a..56
#..f3.06..97.8e..
#...93.da28.bf...
#4.6.bf.9d.35.1.2
#.....27..f0.....
#.....c0..d6.....
#7.8.ea.35.94.f.b
#...62.b413.7c...
#..40.75..b2.d9..
#e0..f9....82..6d
#3.7.4.e..1.0.a.8
#...b........5...
#5.c8..2..a..eb.3

Each line belonging to the grid must start with a hash character, any other line is ignored. The unknown positions must be filled with dots. The last line must be followed by a blank line.
Then you open a command window, you set the default directory to the directory where the files hexadoku.exe, sudoku.ini and 201411.txt reside (all must be in the same), and execute hexadoku.exe with the command :

hexadoku 201411.txt>201411.lst

If no error is reported (usually bad syntax or duplicate digit), a text file named 201411.lst (or whatever you chose to name it) containing the solution is created. Just ignore all the intermediate text (it details the operations the program performs) and go to the end of the file. There you should find the filled out grid :

   0 1 2 3 4 5 6 7 8 9 A B C D E F

0  6 8 2 4 D B 3 5 C E 1 9 7 0 F A
1  C 5 0 7 A E F 2 B 6 D 3 1 8 4 9
2  1 9 3 A 0 6 4 7 F 2 5 8 B C D E
3  B D E F C 8 9 1 0 7 4 A 2 3 5 6
4  D 2 F 3 5 0 6 C A 9 7 1 8 E B 4
5  0 1 5 9 3 4 D A 2 8 E B F 6 7 C
6  4 7 6 E B F 8 9 D C 3 5 0 1 A 2
7  8 A B C 1 2 7 E 4 F 0 6 3 D 9 5
8  2 B 1 5 9 C 0 8 E D 6 F A 4 3 7
9  7 C 8 D E A 1 3 5 0 9 4 6 F 2 B
A  F E 9 6 2 D B 4 1 3 A 7 C 5 8 0
B  A 3 4 0 6 7 5 F 8 B 2 C D 9 E 1
C  E 0 A 1 F 9 C B 3 5 8 2 4 7 6 D
D  3 F 7 2 4 5 E D 6 1 B 0 9 A C 8
E  9 6 D B 8 3 A 0 7 4 C E 5 2 1 F
F  5 4 C 8 7 1 2 6 9 A F D E B 0 3

This program solves the standard 9x9 sudoku grids also. You just have to go through the same process.
The sudoku.ini file is necessary, as it defines the lists of characters that are used as digits.

Downloads : executable, source