Java Reference
In-Depth Information
10
return
;
11 }
12
13
double
result = numbers[
0
];
14
15
for
(
int
i =
1
; i < numbers.length; i++)
16
if
(numbers[i] > result)
17 result = numbers[i];
18
19 System.out.println(
"The max value is "
+ result);
20 }
21 }
Line 3 invokes the
printMax
method with a variable-length argument list passed to the array
numbers
. If no arguments are passed, the length of the array is
0
(line 8).
Line 4 invokes the
printMax
method with an array.
✓
✓
6.17
What is wrong in the following method header?
public static void
print(String... strings,
double
... numbers)
public static void
print(
double
... numbers, String name)
public static double
... print(
double
d1,
double
d2)
Check
Point
6.18
Can you invoke the
printMax
method in Listing 6.5 using the following statements?
printMax(
1
,
2
,
2
,
1
,
4
);
printMax(
new double
[]{
1
,
2
,
3
});
printMax(
new int
[]{
1
,
2
,
3
});
If an array is sorted, binary search is more efficient than linear search for finding an
element in the array.
Key
Point
Searching
is the process of looking for a specific element in an array—for example, discover-
ing whether a certain score is included in a list of scores. Searching is a common task in com-
puter programming. Many algorithms and data structures are devoted to searching. This
section discusses two commonly used approaches,
linear search
and
binary search
.
linear search
binary search
6.10.1 The Linear Search Approach
The linear search approach compares the key element
key
sequentially with each element in
the array. It continues to do so until the key matches an element in the array or the array is
exhausted without a match being found. If a match is made, the linear search returns the index
of the element in the array that matches the key. If no match is found, the search returns
-1
.
The
linearSearch
method in Listing 6.6 gives the solution.
linear search animation on
Companion Website
L
ISTING
6.6
LinearSearch.java
1
public class
LinearSearch {
2
/** The method for finding a key in the list */
3
public static int
linearSearch(
int
[] list,
int
key) {
4
for
(
int
i =
0
; i < list.length; i++) {
5
if
(key == list[i])
6
return
i;
[0] [1] [2] …
7 }
8
list
key Compare key with
list[i]
for
i
= 0, 1, …
return
-
1
;
9 }
10 }
