1
|
1 |
/*
|
670
|
2 |
* Copyright 2006-2008 Sun Microsystems, Inc. All Rights Reserved.
|
1
|
3 |
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
|
|
4 |
*
|
|
5 |
* This code is free software; you can redistribute it and/or modify it
|
|
6 |
* under the terms of the GNU General Public License version 2 only, as
|
|
7 |
* published by the Free Software Foundation.
|
|
8 |
*
|
|
9 |
* This code is distributed in the hope that it will be useful, but WITHOUT
|
|
10 |
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
11 |
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
12 |
* version 2 for more details (a copy is included in the LICENSE file that
|
|
13 |
* accompanied this code).
|
|
14 |
*
|
|
15 |
* You should have received a copy of the GNU General Public License version
|
|
16 |
* 2 along with this work; if not, write to the Free Software Foundation,
|
|
17 |
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
18 |
*
|
|
19 |
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
|
|
20 |
* CA 95054 USA or visit www.sun.com if you need additional information or
|
|
21 |
* have any questions.
|
|
22 |
*
|
|
23 |
*/
|
|
24 |
|
|
25 |
import java.util.*;
|
|
26 |
|
|
27 |
// Copyright 1996, Animorphic Systems
|
|
28 |
// gri 28 Aug 92 / 15 Jan 93 / 8 Dec 95
|
|
29 |
|
|
30 |
class Queens {
|
|
31 |
|
|
32 |
static void try_i(boolean a[], boolean b[], boolean c[], int x[], int i) {
|
|
33 |
int adj = 7;
|
|
34 |
|
|
35 |
for (int j = 1; j <= 8; j++) {
|
|
36 |
if (b[j] && a[i+j] && c[adj+i-j]) {
|
|
37 |
x[i] = j;
|
|
38 |
b[j] = false;
|
|
39 |
a[i+j] = false;
|
|
40 |
c[adj+i-j] = false;
|
|
41 |
if (i < 8) try_i(a, b, c, x, i+1);
|
|
42 |
else print(x);
|
|
43 |
b[j] = true;
|
|
44 |
a[i+j] = true;
|
|
45 |
c[adj+i-j] = true;
|
|
46 |
}
|
|
47 |
}
|
|
48 |
}
|
|
49 |
|
|
50 |
public static void main(String s[]) {
|
|
51 |
boolean a[] = new boolean[16+1];
|
|
52 |
boolean b[] = new boolean[ 8+1];
|
|
53 |
boolean c[] = new boolean[14+1];
|
|
54 |
int x[] = new int[8+1];
|
|
55 |
int adj = 7;
|
|
56 |
|
|
57 |
for (int i = -7; i <= 16; i++) {
|
|
58 |
if (i >= 1 && i <= 8) b[i] = true;
|
|
59 |
if (i >= 2) a[i] = true;
|
|
60 |
if (i <= 7) c[adj+i] = true;
|
|
61 |
}
|
|
62 |
|
|
63 |
x[0] = 0; // solution counter
|
|
64 |
|
|
65 |
try_i(a, b, c, x, 1);
|
|
66 |
}
|
|
67 |
|
|
68 |
static void print(int x[]) {
|
|
69 |
// first correct solution: A1 B5 C8 D6 E3 F7 G2 H4
|
|
70 |
|
|
71 |
char LF = (char)0xA;
|
|
72 |
char CR = (char)0xD;
|
|
73 |
|
|
74 |
x[0]++;
|
|
75 |
if (x[0] < 10)
|
|
76 |
System.out.print(" ");
|
|
77 |
System.out.print(x[0] + ". ");
|
|
78 |
for (int i = 1; i <= 8; i++) {
|
|
79 |
char p = (char)('A' + i - 1);
|
|
80 |
System.out.print(p);
|
|
81 |
System.out.print (x[i] + " ");
|
|
82 |
}
|
|
83 |
System.out.println();
|
|
84 |
}
|
|
85 |
|
|
86 |
};
|