Data Structures and Algorithms in Java[1].pdf - Fulvio Frisone

an array a are numbered 0, 1,2, and so on. We illustrate an array of high scores for a
video game in Figure 1.6.
Figure 1.6: An illustration of an array of ten (int) high
scores for a video game.
Such an organization is quite useful, for it allows us to do some interesting
computations. For example, the following method adds up all the numbers in an array
of integers:
/** Adds all the numbers in an integer array. */
public static int sum(int[] a) {
int total = 0;
for (int i=0; i < a.length; i==) // note the use of the length
variable
total += a[i];
return total;
}
This example takes advantage of a nice feature of Java, which allows us to find the
number of cells an array stores, that is, its length. In Java, an array a is a special kind
of object and the length of a is stored in an instance variable, length. That is, we
never need to guess the length of an array in Java, the length of an array can be
accessed as follows:
array_name.length
where array_name is the name of the array. Thus, the cells of an array a are
numbered 0, 1,2, and so on, up to a.length − 1.
Array Elements and Capacities
Each object stored in an array is called an element of that array. Element number 0
is a[0], element number 1 is a[1], element number 2 is a[2], and so on. Since the
length of an array determines the maximum number of things that can be stored in
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