Version 0.10.0

Critical fix for possible memory hog bug in the connection to the Dancing Links solver.

Author: hbldh

README.md

@@ -11,12 +11,11 @@ Sudoku Solver written in pure Python with no dependencies.
 It solves Sudokus of sizes `N x N` by pure induction as 
 far as is possible, and then uses an optional 
 [Dancing Links](https://en.wikipedia.org/wiki/Dancing_Links) 
-solver, which is a brute force methodology, when the basic 
-induction is not enough. 
+brute force solver, when the basic induction is not enough. 
 
 ## Installation
 
-Install by calling:
+Install with pip:
 
     pip install dlxsudoku
 
@@ -38,7 +37,6 @@ from dlxsudoku import Sudoku
 
 s = Sudoku.load_file('path/to/sudoku.sud')
 s.solve(verbose=True, allow_brute_force=True)
-
 ```
 
 Alternatively, if your Sudoku is stored in string variable 
@@ -68,6 +66,24 @@ print(s2)
 
 ```
 
+**DLXSudoko treats a Sudoku with multiple solutions as a faulty one
+and raises a** ``dlxsudoku.exceptions.SudokuHasMultipleSolutionsError`` 
+**exception in such a situation.**
+
+### Use from terminal
+
+DLXSudoku also installs a console entry point. Can solve Sudokus from string or from path:
+ 
+```shell
+solve-sudoku --sudoku 030467050920010006067300148301006027400850600090200400005624001203000504040030702
+```
+
+or 
+
+```shell
+solve-sudoku --path "path/to/sudoku.sud"
+```
+
 ### Sudoku formatting
 
 A Sudoku file or string should be structured in the following manner:

dlxsudoku/sudoku.py

@@ -226,14 +226,22 @@ def solve(self, verbose=False, allow_brute_force=True):
             # Else, if singles_found is True, run another iteration to see if new singles have shown up.
             if not singles_found:
                 if allow_brute_force:
+                    solution = None
                     try:
                         dlxs = DancingLinksSolver(copy.deepcopy(self._matrix))
-                        solutions = list(dlxs.solve())
-                    except:
+                        solutions = dlxs.solve()
+                        solution = next(solutions)
+                        more_solutions = next(solutions)
+                    except StopIteration as e:
+                        if solution is not None:
+                            self._matrix = solution
+                        else:
+                            raise SudokuHasNoSolutionError("Dancing Links solver could not find any solution.")
+                    except Exception as e:
                         raise SudokuHasNoSolutionError("Brute Force method failed.")
-                    if len(solutions) == 1:
-                        self._matrix = solutions[0]
-                    elif len(solutions) > 1:
+                    else:
+                        # We end up here if the second `next(solutions)` works,
+                        # i.e. if multiple solutions exist.
                         raise SudokuHasMultipleSolutionsError("This Sudoku has multiple solutions!")
                     self.solution_steps.append("BRUTE FORCE - Dancing Links")
                     break

setup.py

@@ -30,7 +30,7 @@
 
 setup(
     name='dlxsudoku',
-    version='0.9.3',
+    version='0.10.0',
     author='Henrik Blidh',
     author_email='[email protected]',
     description='Sudoku Solver in pure Python with no dependencies',