/*
* Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
* cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
* pioneering role in inventing and promulgating (and standardizing) the Java
* language and environment is gratefully acknowledged.
*
* The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
* inventing predecessor languages C and C++ is also gratefully acknowledged.
*/
import java.util.Arrays;
import java.util.Random;
/**
* Array Hunt "game" (pathetic: computer plays itself).
*
* @author Ian Darwin
* @version $Id: ArrayHunt.java,v 1.3 2004/03/08 00:11:18 ian Exp $
*/
public class ArrayHunt {
/** the maximum (and actual) number of random ints to allocate */
protected final static int MAX = 4000;
/** the value to look for */
protected final static int NEEDLE = 1999;
int[] haystack;
Random r;
public static void main(String[] argv) {
ArrayHunt h = new ArrayHunt();
if (argv.length == 0)
h.play();
else {
int won = 0;
int games = Integer.parseInt(argv[0]);
for (int i = 0; i < games; i++)
if (h.play())
++won;
System.out
.println("Computer won " + won + " out of " + games + ".");
}
}
/** Construct the hunting ground */
public ArrayHunt() {
haystack = new int[MAX];
r = new Random();
}
/** Play one game. */
public boolean play() {
int i;
// Fill the array with random data (hay?)
for (i = 0; i < MAX; i++) {
haystack[i] = (int) (r.nextFloat() * MAX);
}
// Precondition for binary search is that data be sorted!
Arrays.sort(haystack);
// Look for needle in haystack
i = Arrays.binarySearch(haystack, NEEDLE);
if (i >= 0) { // Found it, we win.
System.out.println("Value " + NEEDLE + " occurs at haystack[" + i
+ "]");
return true;
} else { // Not found, we lose.
System.out.println("Value " + NEEDLE
+ " does not occur in haystack; nearest value is "
+ haystack[-(i + 2)] + " (found at " + -(i + 2) + ")");
return false;
}
}
}
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