sudoku 0.1.1

A Sudoku solver for Dart

Sudoku Solver

Port of Solving Every Sudoku Puzzle by Peter Norvig in Dart.

• sudoku_solver.dart in Dart
• sudo.py in Python
• Solver.cs in C#
• sudoku.rb in Ruby
• sudoku.coffee in CoffeeScript

View above solutions side-by-side in Python, Dart, C#, Ruby, CoffeeScript.

Example

From Command line:

./bin/sudoku.dart .....6....59.....82....8....45........3........6..3.54...325..6..................

As a Library:

import '../lib/sudoku.dart';

solveSudoku('.....6....59.....82....8....45........3........6..3.54...325..6..................');

Output

Board: .....6....59.....82....8....45........3........6..3.54...325..6..................

4 8 7 |2 5 6 |3 1 9 
6 5 9 |7 3 1 |4 2 8 
2 3 1 |4 9 8 |6 7 5 
------+------+------
9 4 5 |6 1 2 |7 8 3 
7 1 3 |5 8 4 |9 6 2 
8 2 6 |9 7 3 |1 5 4 
------+------+------
1 7 4 |3 2 5 |8 9 6 
3 9 2 |8 6 7 |5 4 1 
5 6 8 |1 4 9 |2 3 7 

solved: true, in 69ms

Benchmarks

Results from running these stand-alone benchmarks on a new 2013 high-end 27" iMac on OSX after a clean re-start. Results are shown in Microseconds (�s):

Side-by-side Results Summary

	grid1	grid2	top95
Dart	1x	1.05x	1x
C# / .NET	1.15x	1x	1.22x
Python	1.20x	1.06x	1.36x
CoffeeScript	1.80x	15.36x	3.62x
C# / Mono	3.73x	3.23x	3.97x
Ruby	1.89x	6.53x	114.55x

Dart

localhost:benchmarks mythz$ dart sudoku.dart 
grid1(RunTime): 3824.091778202677 us.
grid2(RunTime): 8171.428571428572 us.
top95(RunTime): 1160500.0 us.

C# / .NET (in Paralells Windows 8 VM)

C:\Users\mythz\Documents\Visual Studio 2012\Projects\Sudoku\Sudoku\bin\Release>Sudoku.exe
grid1(RunTime): 4402.1978021978 us.
grid2(RunTime): 7816.40625 us.
top95(RunTime): 1415500 us.

Python

localhost:benchmarks mythz$ python sudoku.py 
grid1(RunTime): 4581 us.
grid2(RunTime): 8302 us.
top95(RunTime): 1576500 us.

CoffeeScript

localhost:benchmarks mythz$ coffee sudoku.coffee 
grid1(RunTime): 6893.470790378007 us.
grid2(RunTime): 120058.82352941176 us.
top95(RunTime): 4199000 us.

C# / Mono

localhost:benchmarks mythz$ dmcs -optimize sudoku.cs 
localhost:benchmarks mythz$ mono sudoku.exe 
grid1(RunTime): 14269.5035460993 us.
grid2(RunTime): 25275 us.
top95(RunTime): 4606000 us.

Ruby

localhost:benchmarks mythz$ /usr/local/Cellar/ruby/2.0.0-p0/bin/ruby sudoku.rb 
grid1(RunTime): 7189.8172043010745 us.
grid2(RunTime): 51023.675 us.
top95(RunTime): 132935387.99999997 us.

Benchmark Notes

Unlike many benchmarks these stand-alone ports weren't written with performance in mind. i.e They were designed to show a readable and expressive example of Peter Norvig's original Python solution available in each language. These benchmarks then only show the performace of each languages contained 'readable style'.

I added the benchmark harness used in each port, which was originally based on Dart's benchmark_harness that is currently being used to measure Dart's performance. i.e. There's a 100ms warmup, before running the specific benchmark for 2000ms, then returning the avg time for each iteration in Microseconds (�s). Whilst I aimed to keep the implementation of each benchmark harness as close as possible, if there is a more accurate / high-precision (stand-alone) method available please send in a pull-request and I'll update the results.

The 'Hard1' board benchmarks

Peter Norvig's hard1 sample board was run in isolation since in most cases each took a lot longer than the 2s run rate being sampled above. In addition to the performace results varying significantly, most found different correct solutions to the same board (i.e. only Python / C# returned same board). The results however are deterministic, i.e. each run results in the same board being returned within the same time-frame.

Dart

localhost:benchmarks mythz$ dart sudoku.dart 

hard1: .....6....59.....82....8....45........3........6..3.54...325..6..................
4 8 7 |2 5 6 |3 1 9 
6 5 9 |7 3 1 |4 2 8 
2 3 1 |4 9 8 |6 7 5 
------+------+------
9 4 5 |6 1 2 |7 8 3 
7 1 3 |5 8 4 |9 6 2 
8 2 6 |9 7 3 |1 5 4 
------+------+------
1 7 4 |3 2 5 |8 9 6 
3 9 2 |8 6 7 |5 4 1 
5 6 8 |1 4 9 |2 3 7 

solved: true, in 67ms

C# / .NET (in Paralells Windows 8 VM)

C:\Users\mythz\Documents\Visual Studio 2012\Projects\Sudoku\Sudoku\bin\Release>Sudoku.exe
hard1: .....6....59.....82....8....45........3........6..3.54...325..6..................
4 3 8 |7 9 6 |2 1 5
6 5 9 |1 3 2 |4 7 8
2 7 1 |4 5 8 |6 9 3
------+------+------
8 4 5 |2 1 9 |3 6 7
7 1 3 |5 6 4 |8 2 9
9 2 6 |8 7 3 |1 5 4
------+------+------
1 9 4 |3 2 5 |7 8 6
3 6 2 |9 8 7 |5 4 1
5 8 7 |6 4 1 |9 3 2

solved: True, in 50079ms

Python

localhost:benchmarks mythz$ python sudoku.py 

hard1: .....6....59.....82....8....45........3........6..3.54...325..6..................
4 3 8 |7 9 6 |2 1 5 
6 5 9 |1 3 2 |4 7 8 
2 7 1 |4 5 8 |6 9 3 
------+------+------
8 4 5 |2 1 9 |3 6 7 
7 1 3 |5 6 4 |8 2 9 
9 2 6 |8 7 3 |1 5 4 
------+------+------
1 9 4 |3 2 5 |7 8 6 
3 6 2 |9 8 7 |5 4 1 
5 8 7 |6 4 1 |9 3 2 

solved: True, in 80425.67 ms

C# / Mono

localhost:benchmarks mythz$ dmcs -optimize sudoku.cs 
localhost:benchmarks mythz$ mono sudoku.exe 
hard1: .....6....59.....82....8....45........3........6..3.54...325..6..................
4 3 8 |7 9 6 |2 1 5 
6 5 9 |1 3 2 |4 7 8 
2 7 1 |4 5 8 |6 9 3 
------+------+------
8 4 5 |2 1 9 |3 6 7 
7 1 3 |5 6 4 |8 2 9 
9 2 6 |8 7 3 |1 5 4 
------+------+------
1 9 4 |3 2 5 |7 8 6 
3 6 2 |9 8 7 |5 4 1 
5 8 7 |6 4 1 |9 3 2 

solved: True, in 162868ms

Ruby

localhost:benchmarks mythz$ /usr/local/Cellar/ruby/2.0.0-p0/bin/ruby sudoku.rb 

hard1: .....6....59.....82....8....45........3........6..3.54...325..6..................
------+------+------
4 6 2 |8 7 9 |1 3 5 
3 5 7 |4 1 2 |9 6 8 
8 9 1 |5 3 6 |4 2 7 
------+------+------
7 1 4 |2 5 8 |3 9 6 
9 3 5 |1 6 7 |2 8 4 
6 2 8 |9 4 3 |5 7 1 
------+------+------
2 4 6 |3 8 1 |7 5 9 
1 7 9 |6 2 5 |8 4 3 
5 8 3 |7 9 4 |6 1 2 
------+------+------
solved: true, in 247882.09100000001ms

CoffeeScript

Ran for over 1hr, but never finished. 

Contributors

• mythz (Demis Bellot)

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Contributions for more languages or to make the existing ports more idiomatic are welcome.