queensgui/src/queens.cpp

/***************************************************************************
 *   Copyright (C) 2005 by Torben Nielsen   *
 *   torben@t-hoerup.dk   *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include "solution.h"
#include "queens.h"
#include "solutioncontainer.h"


Queens::Queens(GUIUpdate *par, SolutionContainer *sol, int set_size, bool set_debug) : QThread(), solution(set_size)
{
        parent = par;
        size = set_size;
        solution.setSize(size);
        debug = set_debug;
        solutions = sol;
}

bool Queens::solve()
{
        return solve(0, false);
}

void Queens::findAll()
{
        solve(0,true);
}

bool Queens::solve(int row, bool findAll)
{
        if (blocked == true)
                return false;
        for (int col=0; col<size; col++) {
                if (checkCols(row,col) == true && 
                                checkCross1(row,col) == true && 
                                checkCross2(row,col) == true) {

                        solution.matrix[row][col] = true;
                        
                        if (row == (size-1) ) {
                                if (!findAll)
                                        return true;
                                else {
                                        solutions->addSolution( solution );
                                        parent->foundSolution();
                                }
                        }

                        if ( solve(row+1,findAll) )
                                return true;

                        solution.matrix[row][col] = false;
                }
        }
        return false;
}


bool Queens::checkRows(int row, int col)
{
        for (int c=0; c<size; c++) {
                if (solution.matrix[row][c] == true)
                        return false;
        }
                
        return true;
}

bool Queens::checkCols(int row, int col)
{
        for (int r=0; r<size; r++) {
                if (solution.matrix[r][col] == true)
                        return false;
        }
        return true;
}

bool Queens::checkCross1(int row, int col)
{
        int r=row;
        int c=col;
        for (int i=0; i<size; i++) {
                if (solution.matrix[r][c] == true)
                        return false;
                r++;
                c++;
                if ( r>(size-1) || c>(size-1) )
                        break;          
        }
        r=row;
        c=col;
        for (int i=0; i<size;i++) {
                if (solution.matrix[r][c] == true)
                        return false;
                r--;
                c--;
                if (r<0 || c<0)
                        break;
        }
        return true;
}

bool Queens::checkCross2(int row, int col)
{
        int r=row;
        int c=col;
        for (int i=0; i<size; i++) {
                if (solution.matrix[r][c] == true)
                        return false;
                r++;
                c--;
                if ( r>(size-1) || c<0 )
                        break;
        }
        r=row;
        c=col;
        for (int i=0; i<size; i++) {
                if (solution.matrix[r][c] == true)
                        return false;
                r--;
                c++;
                if (r<0 || c>(size-1))
                        break;
        }
        return true;
}

void Queens::run()
{
        blocked = false;
        findAll();
        
        if (blocked == false)
                parent->finishedSearch();
}

void Queens::stop()
{
        blocked = true;
}
1	/***************************************************************************
2	* Copyright (C) 2005 by Torben Nielsen *
3	* torben@t-hoerup.dk *
4	* *
5	* This program is free software; you can redistribute it and/or modify *
6	* it under the terms of the GNU General Public License as published by *
7	* the Free Software Foundation; either version 2 of the License, or *
8	* (at your option) any later version. *
9	* *
10	* This program is distributed in the hope that it will be useful, *
11	* but WITHOUT ANY WARRANTY; without even the implied warranty of *
12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
13	* GNU General Public License for more details. *
14	* *
15	* You should have received a copy of the GNU General Public License *
16	* along with this program; if not, write to the *
17	* Free Software Foundation, Inc., *
18	* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
19	***************************************************************************/
20
21	#include "solution.h"
22	#include "queens.h"
23	#include "solutioncontainer.h"
24
25
26	Queens::Queens(GUIUpdate par, SolutionContainer sol, int set_size, bool set_debug) : QThread(), solution(set_size)
27	{
28	parent = par;
29	size = set_size;
30	solution.setSize(size);
31	debug = set_debug;
32	solutions = sol;
33	}
34
35	bool Queens::solve()
36	{
37	return solve(0, false);
38	}
39
40	void Queens::findAll()
41	{
42	solve(0,true);
43	}
44
45	bool Queens::solve(int row, bool findAll)
46	{
47	if (blocked == true)
48	return false;
49	for (int col=0; col<size; col++) {
50	if (checkCols(row,col) == true &&
51	checkCross1(row,col) == true &&
52	checkCross2(row,col) == true) {
53
54	solution.matrix[row][col] = true;
55
56	if (row == (size-1) ) {
57	if (!findAll)
58	return true;
59	else {
60	solutions->addSolution( solution );
61	parent->foundSolution();
62	}
63	}
64
65	if ( solve(row+1,findAll) )
66	return true;
67
68	solution.matrix[row][col] = false;
69	}
70	}
71	return false;
72	}
73
74
75	bool Queens::checkRows(int row, int col)
76	{
77	for (int c=0; c<size; c++) {
78	if (solution.matrix[row][c] == true)
79	return false;
80	}
81
82	return true;
83	}
84
85	bool Queens::checkCols(int row, int col)
86	{
87	for (int r=0; r<size; r++) {
88	if (solution.matrix[r][col] == true)
89	return false;
90	}
91	return true;
92	}
93
94	bool Queens::checkCross1(int row, int col)
95	{
96	int r=row;
97	int c=col;
98	for (int i=0; i<size; i++) {
99	if (solution.matrix[r][c] == true)
100	return false;
101	r++;
102	c++;
103	if ( r>(size-1) \|\| c>(size-1) )
104	break;
105	}
106	r=row;
107	c=col;
108	for (int i=0; i<size;i++) {
109	if (solution.matrix[r][c] == true)
110	return false;
111	r--;
112	c--;
113	if (r<0 \|\| c<0)
114	break;
115	}
116	return true;
117	}
118
119	bool Queens::checkCross2(int row, int col)
120	{
121	int r=row;
122	int c=col;
123	for (int i=0; i<size; i++) {
124	if (solution.matrix[r][c] == true)
125	return false;
126	r++;
127	c--;
128	if ( r>(size-1) \|\| c<0 )
129	break;
130	}
131	r=row;
132	c=col;
133	for (int i=0; i<size; i++) {
134	if (solution.matrix[r][c] == true)
135	return false;
136	r--;
137	c++;
138	if (r<0 \|\| c>(size-1))
139	break;
140	}
141	return true;
142	}
143
144	void Queens::run()
145	{
146	blocked = false;
147	findAll();
148
149	if (blocked == false)
150	parent->finishedSearch();
151	}
152
153	void Queens::stop()
154	{
155	blocked = true;
156	}