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/*
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* Copyright 2006 Sun Microsystems, Inc. All Rights Reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*
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*/
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import java.util.*;
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// Copyright 1996, Animorphic Systems
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// gri 28 Aug 92 / 15 Jan 93 / 8 Dec 95
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class Queens {
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static void try_i(boolean a[], boolean b[], boolean c[], int x[], int i) {
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int adj = 7;
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for (int j = 1; j <= 8; j++) {
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if (b[j] && a[i+j] && c[adj+i-j]) {
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x[i] = j;
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b[j] = false;
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a[i+j] = false;
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c[adj+i-j] = false;
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if (i < 8) try_i(a, b, c, x, i+1);
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else print(x);
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b[j] = true;
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a[i+j] = true;
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c[adj+i-j] = true;
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}
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}
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}
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public static void main(String s[]) {
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boolean a[] = new boolean[16+1];
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boolean b[] = new boolean[ 8+1];
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boolean c[] = new boolean[14+1];
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int x[] = new int[8+1];
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int adj = 7;
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for (int i = -7; i <= 16; i++) {
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if (i >= 1 && i <= 8) b[i] = true;
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if (i >= 2) a[i] = true;
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if (i <= 7) c[adj+i] = true;
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}
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x[0] = 0; // solution counter
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try_i(a, b, c, x, 1);
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}
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static void print(int x[]) {
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// first correct solution: A1 B5 C8 D6 E3 F7 G2 H4
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char LF = (char)0xA;
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char CR = (char)0xD;
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x[0]++;
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if (x[0] < 10)
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System.out.print(" ");
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System.out.print(x[0] + ". ");
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for (int i = 1; i <= 8; i++) {
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char p = (char)('A' + i - 1);
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System.out.print(p);
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System.out.print (x[i] + " ");
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}
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System.out.println();
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}
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};
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