Java Reference
In-Depth Information
filled it with random numbers, it isn't initially sorted. Hence, we call
Arrays.sort()
on the
array. Then we are in a position to call
Arrays.binarySearch()
, passing in the array and
the value to look for. If you run the program with a number, it runs that many games and re-
ports on how it fared overall. If you don't bother, it plays only one game:
public
public class
ArrayHunt
{
/** the maximum (and actual) number of random ints to allocate */
protected
class
ArrayHunt
protected final
final static
static
int
int
MAX
=
4000
;
/** the value to look for */
protected
protected final
final static
static
int
int
NEEDLE
=
1999
;
int
int
[]
haystack
;
Random r
;
public
public static
void
main
(
String
[]
argv
) {
ArrayHunt h
=
new
static
void
new
ArrayHunt
();
iif
(
argv
.
length
==
0
)
h
.
play
();
else
else
{
int
int
won
=
0
;
int
int
games
=
Integer
.
parseInt
(
argv
[
0
]);
for
int
i
=
0
;
i
<
games
;
i
++)
iif
(
h
.
play
())
++
won
;
System
.
out
.
println
(
"Computer won "
+
won
+
" out of "
+
games
+
"."
);
for
(
int
}
}
/** Construct the hunting ground */
public
public
ArrayHunt
() {
haystack
=
new
new
int
int
[
MAX
];
r
=
new
new
Random
();
}
/** Play one game. */
public
public
boolean
boolean
play
() {
int
int
i
;
// Fill the array with random data (hay?)
for
for
(
i
=
0
;
i
<
MAX
;
i
++) {
haystack
[
i
] = (
int
int
)(
r
.
nextFloat
() *
MAX
);
}
// Precondition for binary search is that data be sorted!
