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/*
* Copyright (c) 2006, 2008, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
import java.util.*;
// Copyright 1996, Animorphic Systems
// gri 28 Aug 92 / 15 Jan 93 / 8 Dec 95
class Queens {
static void try_i(boolean a[], boolean b[], boolean c[], int x[], int i) {
int adj = 7;
for (int j = 1; j <= 8; j++) {
if (b[j] && a[i+j] && c[adj+i-j]) {
x[i] = j;
b[j] = false;
a[i+j] = false;
c[adj+i-j] = false;
if (i < 8) try_i(a, b, c, x, i+1);
else print(x);
b[j] = true;
a[i+j] = true;
c[adj+i-j] = true;
}
}
}
public static void main(String s[]) {
boolean a[] = new boolean[16+1];
boolean b[] = new boolean[ 8+1];
boolean c[] = new boolean[14+1];
int x[] = new int[8+1];
int adj = 7;
for (int i = -7; i <= 16; i++) {
if (i >= 1 && i <= 8) b[i] = true;
if (i >= 2) a[i] = true;
if (i <= 7) c[adj+i] = true;
}
x[0] = 0; // solution counter
try_i(a, b, c, x, 1);
}
static void print(int x[]) {
// first correct solution: A1 B5 C8 D6 E3 F7 G2 H4
char LF = (char)0xA;
char CR = (char)0xD;
x[0]++;
if (x[0] < 10)
System.out.print(" ");
System.out.print(x[0] + ". ");
for (int i = 1; i <= 8; i++) {
char p = (char)('A' + i - 1);
System.out.print(p);
System.out.print (x[i] + " ");
}
System.out.println();
}
};
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