view make/test/Queens.java @ 6972:bd7a7ce2e264

6830717: replay of compilations would help with debugging Summary: When java process crashed in compiler thread, repeat the compilation process will help finding root cause. This is done with using SA dump application class data and replay data from core dump, then use debug version of jvm to recompile the problematic java method. Reviewed-by: kvn, twisti, sspitsyn Contributed-by: yumin.qi@oracle.com
author minqi
date Mon, 12 Nov 2012 14:03:53 -0800
parents c18cbe5936b8
children
line wrap: on
line source

/*
 * 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();
  }

};