Arrays with Loops
Learn to use arrays with the help of loops in Java.
The for
loop with arrays
The individual values in an array are accessed through an index number. The for
loop variable can be used as an index number. However, the array values can also be used directly in a for
loop.
The following program demonstrates the various ways of accessing array elements:
class Test{public static void main(String[] args){String[] vals = {"-5", "Java", "3.8"};System.out.println("One way of printing an array: ");for (int i = 0; i < vals.length; i++){System.out.println(vals[i]);}System.out.println("Another way of printing an array: ");for (String s: vals){System.out.println(s);}}}
In the code above:
- The new item is the
vals.length
function, which is used to get the length of the array. - The first
for
loop accesses the array values with the help of the loop variablei
. - The second
for
loop directly accesses the array values.
The while
loop with arrays
We usually use the while
loop to deal with arrays when the number of iterations is not fixed. For example, let’s say we want to generate n
terms of a Fibonacci sequence and store it in an array, where n
is the user input. A Fibonacci sequence is a sequence in which each number is the sum of the two preceding ones, except the first two terms.
Let’s start by noting a few terms of this sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ….
Here’s how to solve this problem:
- Start with an empty array of