Java how can i add a pair of numbers to an arraylist

To add a pair of numbers to an ArrayList in Java, you can use the add method of the ArrayList class to add the numbers as elements to the list.

Here is an example of how to add a pair of numbers to an ArrayList in Java:

List<Integer> list = new ArrayList<>();

int a = 10;
int b = 20;

list.add(a);
list.add(b);

System.out.println(list);

In this example, the list variable is defined as an ArrayList of integers, and the ArrayList class is used to instantiate the list. The a and b variables are defined as integers and initialized with the values 10 and 20, respectively. The add method is used to add the a and b variables to the list, and the System.out.println method is used to print the list to the console.

You can use this approach to add a pair of numbers to an ArrayList in Java by defining an ArrayList and using the add method to add the numbers as elements to the list. You can also customize this approach by using different types of numbers, such as integers, floats, or doubles, or by using different methods to add the numbers to the list.

Note that you can also use the addAll method of the ArrayList class to add multiple elements to the list at once, or the Collections.addAll method to add an array of elements to the list.

List<Integer> list = new ArrayList<>();

int[] numbers = {10, 20};
list.addAll(Arrays.asList(numbers));

System.out.println(list);

In this example, the numbers array is defined as an array of integers and initialized with the values 10 and 20, and the addAll method is used to add the elements of the array to the list. The Arrays.asList method is used to convert the array to a list, and the System.out.println method is used to print the list to the console.