Chapter 2 Question 2.1, Introduction to Java Programming, Tenth Edition Y. Daniel LiangY.

(Convert Celsius to Fahrenheit) Write a program that reads a Celsius degree in a double value from the console, then converts it to Fahrenheit and displays the result. The formula for the conversion is as follows: 

Fahrenheit = (9 / 5) * Celsius + 32 

Hint: In Java, 9 / 5 is 1, but 9.0 / 5 is 1.8.

Solution

import java.util.Scanner;

public class HelloWorld

{

    public static void main(String[] args)

    {

        // Create new Scanner object

        Scanner input = new Scanner(System.in);

        // Prompt user to input a double

        System.out.print("Enter a degree in Celsius: ");

        double celsius = input.nextDouble();

        // Convert Celsius to Fahrenheit

        double fahrenheit = 9.0 / 5 * celsius + 32;

        // Display results

        System.out.println(celsius + " Celsius is " + fahrenheit

            + " Fahrenheit");

    }

}

OUTPUT

Enter a degree in Celsius: 12

12.0 Celsius is 53.6 Fahrenheit);

In this program the background knowledge which we have to acquire to solve this program is using:

fahrenheit = 9.0 / 5 * celsius + 32

Note: 9.0 is a double number.

In java there are Rules of Operator Precedence. And the arithmetic operations are preformed according to it.

Note: As  System.out.println();  is used, therefore the value of Area and Perimeter gets printed in the new line.