Sudoku::Solver Class Reference

Implementation of a backtracking algorithm to solve Sudoku puzzles. More...

#include <solver.h>

Inheritance diagram for Sudoku::Solver:

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Collaboration diagram for Sudoku::Solver:

[legend]

List of all members.

Public Member Functions
	Solver (Puzzle &puzzle, bool random_init=false, unsigned int max_iter=0)
	Constructor.
virtual void	set_first_at (unsigned int level)
	Set the element to the first sibling.
virtual void	set_next_at (unsigned int level)
	Set the element to the next sibling.
virtual void	reset_at (unsigned int level)
	Reset the element.
virtual bool	is_last_at (unsigned int level) const
	Check if the element is set to the last sibling.
virtual bool	is_valid_at (int level) const
	Check if the element is valid (following elements ignored).
virtual bool	is_last_level (int level) const
	Check if the level is the last possible level.
Private Attributes
Puzzle &	puzzle
Pos	free_list [SDIM]
unsigned int	free_count
bool	random_init
bool	random

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Detailed Description

Implementation of a backtracking algorithm to solve Sudoku puzzles.

The algorithm tries to set numbers in all free cells of the puzzle sticking to the rules of Sudoku puzzles.

There are three ways to use this class:

1. Solve a Sudoku puzzle with some numbers given:

    Puzzle puzzle(36); // Generate a random puzzle with 36 givens.
    Solver solver(puzzle);
    solver.find_next_solution();
    if (solver.solution_is_valid())
    {
      // Do something with the puzzle.
      ...
    }
    solver.find_next_solution();
    bool more_than_one_solution = solver.solution_is_valid();

2. Search a random Sudoku solution:

    Puzzle puzzle; // Generate an empty puzzle without givens.
    Solver solver(puzzle, true);
    solver.find_next_solution();
    if (solver.solution_is_valid())
    {
      // Do something with the puzzle.
      ...
    }

3. Search all Sudoku solutions:

    Puzzle puzzle; // Generate an empty puzzle without givens.
    Solver solver(puzzle);
    solver.find_next_solution();
    while (solver.solution_is_valid())
    {
      // Do something with the puzzle.
      ...
      solver.find_next_solution();
    }

Definition at line 83 of file solver.h.

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Constructor & Destructor Documentation

Solver::Solver	(	Puzzle &	puzzle,
		bool	random_init = false,
		unsigned int	max_iter = 0
	)

Constructor.

Definition at line 34 of file solver.cpp.

References Sudoku::Pos::first(), free_count, Sudoku::Puzzle::given(), and Sudoku::Pos::last().

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Member Function Documentation

bool Solver::is_last_at

(

unsigned int

level

)

const [virtual]

Check if the element is set to the last sibling.

Implements BackTrack::Solution.

Definition at line 88 of file solver.cpp.

References free_count, free_list, Sudoku::Puzzle::next_number(), and puzzle.

bool Solver::is_last_level

(

int

level

)

const [virtual]

Check if the level is the last possible level.

Implements BackTrack::Solution.

Definition at line 104 of file solver.cpp.

References free_count.

bool Solver::is_valid_at

(

int

level

)

const [virtual]

Check if the element is valid (following elements ignored).

Implements BackTrack::Solution.

Definition at line 95 of file solver.cpp.

References Sudoku::Puzzle::error(), free_count, free_list, puzzle, and Sudoku::Puzzle::solved().

void Solver::reset_at

(

unsigned int

level

)

[virtual]

Reset the element.

Implements BackTrack::Solution.

Definition at line 80 of file solver.cpp.

References free_count, free_list, puzzle, random, and Sudoku::Puzzle::set().

void Solver::set_first_at

(

unsigned int

level

)

[virtual]

Set the element to the first sibling.

Implements BackTrack::Solution.

Definition at line 44 of file solver.cpp.

References free_count, free_list, Sudoku::Pos::last(), Sudoku::Puzzle::next_cell(), Sudoku::Puzzle::next_number(), Sudoku::Puzzle::numbers_count(), puzzle, random, random_init, and Sudoku::Puzzle::set().

void Solver::set_next_at

(

unsigned int

level

)

[virtual]

Set the element to the next sibling.

Implements BackTrack::Solution.

Definition at line 70 of file solver.cpp.

References free_count, free_list, Sudoku::Puzzle::next_number(), puzzle, and Sudoku::Puzzle::set().

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Member Data Documentation

unsigned int Sudoku::Solver::free_count [private]

Definition at line 87 of file solver.h.

Referenced by is_last_at(), is_last_level(), is_valid_at(), reset_at(), set_first_at(), set_next_at(), and Solver().

Pos Sudoku::Solver::free_list[SDIM] [private]

Definition at line 86 of file solver.h.

Referenced by is_last_at(), is_valid_at(), reset_at(), set_first_at(), and set_next_at().

Puzzle& Sudoku::Solver::puzzle [private]

Definition at line 85 of file solver.h.

Referenced by is_last_at(), is_valid_at(), reset_at(), set_first_at(), and set_next_at().

bool Sudoku::Solver::random [private]

Definition at line 88 of file solver.h.

Referenced by reset_at(), and set_first_at().

bool Sudoku::Solver::random_init [private]

Definition at line 88 of file solver.h.

Referenced by set_first_at().

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The documentation for this class was generated from the following files:

• solver.h
• solver.cpp