Arithmetic Demo 1

Using Arithmetic Operators

In these steps, you create a program that uses arithmetic operators.

1. Open a new file in your text editor, and type the import statement needed for interactive input wiht the Scanner class:

import java.util.Scanner;

2. Type the class header and its curly braces for a class named ArithmeticDemo. Within the class's curly braces, enter the main() method header and its braces.

public class ArithmeticDemo
{
public static void main(String[] args)
{
}
}

3. With the main() method, declare five int variables that will be used to hold two input values and their sum, difference, and average:

int firstNumber;
int secondNumber;
int sum;
int difference;
int average;

4. Also declare a Scanner object so that keyboard input can be accepted.

Scanner input = new Scanner(System.in);

5. Prompt the user for and accept two integers:

System.out.print("Please enter an integer>> ");
firstNumber = input.nextInt();
System.out.print("Please enter another integer>> ");
secondNumber = input.nextInt();

6. Add statements to perform the necessary arithmetic operations:

sum = firstNumber + secondNumber;
difference = firstNumber - secondNumber;
average = sum / 2;

7. Display the three calculated values:

System.out.println(firstNumber + " + " + secondNumber + " is " + sum);
System.out.println(firstNumber + " - " + secondNumber + " is " + difference);
System.out.println("The average of " + firstNumber + " and " + secondNumber + " is " + average);

8. Save the file as ArithmeticDemo.java, and then compile and execute it. Enter values of your choice. Figure 2-38 shows a typical execution. Notice that because integer division was used to compute the average, the answer is an integer.

Figure 2-38 Typical execution ArithmeticDemo application see image.

9. Execute the program multiple times using various integer values and confirm that the results are accurate.