- Checker
- Basic (stupid) solver
- Advanced (backtrack) solver
- Command-line interface for composing puzzles
- Basic sudoku problem generator
- Android app
make
$ ./sudoku_checker # ./sudoku_solver # ./sudoku_advanced
3
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
$ ./sudoku_ui
3
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
- Arrows to navigate
- ENTER to evaluate status
- ESC to leave
3
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
- Numbers to set the value
- TAB to complete the cell for a unique solution
3
0 0 0 0 0 0 0 1 2
0 0 0 0 0 0 0 0 3
0 0 2 3 0 0 4 0 0
0 0 1 8 0 0 0 0 5
0 6 0 0 7 0 8 0 0
0 0 0 0 0 9 0 0 0
0 0 8 5 0 0 0 0 0
9 0 0 0 4 0 5 0 0
4 7 0 0 0 6 0 0 0
$ time ( ./sudoku_generator 5 )
5
0 2 0 0 0 9 17 0 10 13 18 0 15 0 25 4 14 1 0 0 0 0 0 5 0
0 4 0 0 0 3 21 0 0 0 1 0 0 0 0 0 0 0 10 0 17 0 0 11 0
1 0 0 6 20 0 0 16 0 23 0 0 24 0 17 11 22 12 2 0 0 0 0 7 13
3 16 0 0 13 0 1 0 11 4 0 0 20 19 10 6 0 0 0 0 0 25 0 0 0
5 0 0 7 0 18 0 0 12 0 0 0 23 0 0 17 20 0 0 0 21 22 19 1 0
0 0 0 12 3 0 0 17 22 0 9 0 6 0 0 16 11 24 0 0 0 1 0 15 0
0 10 4 23 25 0 14 13 3 0 0 0 0 21 0 7 8 0 0 0 6 9 0 0 19
0 11 19 0 21 12 0 0 0 9 24 5 0 8 0 0 1 20 22 0 4 16 0 0 10
0 0 0 18 16 0 8 20 0 2 14 0 0 25 19 0 10 0 21 17 0 23 0 24 0
0 0 0 0 24 0 0 0 21 0 23 3 4 0 0 18 0 6 0 0 0 0 0 0 0
0 0 2 0 0 0 4 0 19 0 25 1 0 14 0 0 16 23 0 0 8 11 0 0 0
0 0 0 0 15 0 16 10 23 0 22 0 0 0 0 12 0 0 7 0 0 13 9 0 0
0 20 0 0 6 0 0 0 25 21 0 0 19 0 23 0 3 0 4 0 22 0 7 10 1
4 13 9 16 12 14 0 0 0 3 10 8 2 7 0 0 0 0 0 0 23 24 0 17 5
23 0 3 0 18 7 6 12 0 8 13 0 9 0 0 0 5 0 0 0 19 0 16 0 0
0 0 17 2 0 0 0 0 6 7 20 0 0 0 1 19 23 0 11 10 0 0 0 21 0
25 0 0 21 0 13 0 1 17 5 7 0 0 0 0 0 0 18 9 2 11 0 3 0 0
0 0 13 0 0 23 11 0 0 0 0 0 0 6 5 0 4 16 0 0 0 0 0 19 14
0 0 23 0 0 0 20 0 4 0 2 15 18 0 8 14 21 0 0 0 10 0 0 22 0
16 3 14 0 0 0 0 24 0 0 4 0 0 11 0 15 0 22 5 7 20 2 0 23 0
15 0 22 0 2 20 0 11 16 14 6 10 7 0 24 1 13 9 0 4 0 19 0 0 0
19 0 5 13 0 0 12 18 0 17 0 0 0 0 0 0 6 14 0 0 24 7 10 0 15
18 0 0 3 0 0 19 23 0 0 0 20 0 1 0 5 0 7 24 0 0 17 0 13 4
11 23 20 4 0 0 0 0 13 24 0 2 21 0 0 10 0 0 0 3 0 0 0 0 9
0 0 6 10 0 1 2 4 0 0 0 25 13 17 0 21 18 8 0 20 0 3 0 14 22
( ./sudoku_generator 5; ) 33.32s user 0.23s system 98% cpu 33.976 total
Now, we will check how hard it is for the advanced solver to finish:
$ time ( ./sudoku_advanced < input.txt )
21 2 12 11 19 9 17 7 10 13 18 6 15 22 25 4 14 1 8 16 3 20 24 5 23
22 4 18 9 23 3 21 19 20 25 1 7 8 2 12 13 24 5 10 15 17 6 14 11 16
1 8 25 6 20 15 5 16 14 23 21 9 24 3 17 11 22 12 2 19 18 10 4 7 13
3 16 24 17 13 22 1 8 11 4 5 14 20 19 10 6 7 21 18 23 15 25 2 9 12
5 14 15 7 10 18 24 2 12 6 11 16 23 13 4 17 20 25 3 9 21 22 19 1 8
20 5 8 12 3 4 23 17 22 19 9 18 6 10 2 16 11 24 13 14 7 1 21 15 25
17 10 4 23 25 24 14 13 3 1 12 22 11 21 16 7 8 2 15 5 6 9 20 18 19
2 11 19 14 21 12 18 6 7 9 24 5 17 8 15 23 1 20 22 25 4 16 13 3 10
6 9 7 18 16 5 8 20 15 2 14 13 1 25 19 3 10 4 21 17 12 23 22 24 11
13 22 1 15 24 16 10 25 21 11 23 3 4 20 7 18 9 6 19 12 14 5 8 2 17
10 7 2 22 5 17 4 9 19 18 25 1 3 14 21 24 16 23 6 13 8 11 15 12 20
14 19 21 1 15 11 16 10 23 20 22 4 5 24 18 12 2 17 7 8 25 13 9 6 3
8 20 11 24 6 2 13 5 25 21 17 12 19 16 23 9 3 15 4 18 22 14 7 10 1
4 13 9 16 12 14 22 15 1 3 10 8 2 7 6 25 19 11 20 21 23 24 18 17 5
23 17 3 25 18 7 6 12 24 8 13 11 9 15 20 22 5 10 14 1 19 21 16 4 2
9 15 17 2 22 8 25 14 6 7 20 24 16 12 1 19 23 3 11 10 13 4 5 21 18
25 6 10 21 4 13 15 1 17 5 7 19 14 23 22 20 12 18 9 2 11 8 3 16 24
12 18 13 20 7 23 11 21 2 22 3 17 10 6 5 8 4 16 1 24 9 15 25 19 14
24 1 23 5 11 19 20 3 4 16 2 15 18 9 8 14 21 13 25 6 10 12 17 22 7
16 3 14 19 8 10 9 24 18 12 4 21 25 11 13 15 17 22 5 7 20 2 1 23 6
15 12 22 8 2 20 3 11 16 14 6 10 7 18 24 1 13 9 17 4 5 19 23 25 21
19 25 5 13 1 21 12 18 9 17 8 23 22 4 3 2 6 14 16 11 24 7 10 20 15
18 21 16 3 14 6 19 23 8 10 15 20 12 1 9 5 25 7 24 22 2 17 11 13 4
11 23 20 4 17 25 7 22 13 24 16 2 21 5 14 10 15 19 12 3 1 18 6 8 9
7 24 6 10 9 1 2 4 5 15 19 25 13 17 11 21 18 8 23 20 16 3 12 14 22
( ./sudoku_advanced < input.txt; ) 18.04s user 0.04s system 99% cpu 18.157 total
./test_all
$ for i in {1..10000}; do ./sudoku_generator 3 > input.txt; time ( ./sudoku_solver <input.txt >/dev/null ); done 2>&1 | cut -d ' ' -f 15 | sort -n --reverse | head
0.197
0.059
0.056
0.049
0.049
0.044
0.037
0.037
0.034
0.034
$ for i in {1..1000}; do ./sudoku_generator 4 > input.txt; time ( ./sudoku_advanced <input.txt >/dev/null ); done 2>&1 | cut -d ' ' -f 15 | sort -n --reverse | head
0.072
0.064
0.059
0.058
0.050
0.045
0.044
0.043
0.039
0.035
-
Checker: none, it's useless
-
Basic solver:
- Possible values stored in bits
- Recursion heuristics for least possibilities on a cell
-
Advanced solver:
- Algorithm X
- Arrays instead of sparse matrices
- Forward heuristics: minimal number of solutions for a constraint
- Error heuristics: maximum number of deadends for the constraint
-
Puzzle composer:
- ncurses + advanced solver
- Arrows
- Setting/unsetting values
- Validation
- Completion (of a particular cell)
- Exit
-
Puzzle generator:
- Puts random values into sudoku, solves it, and unsets random values
- Uses advanced solver
- Uses
clock(3)to evaluate the difficulty.
Submitted as a 2-week coursework for CS2002 at the University of St Andrews.