COMPUTER PROGRAMMING
Lab(4)
Exercise 1
2.1 (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.
Source code:
import java.util.Scanner;
public class Exercise02_01 {
// Main method
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
// Enter a temperature in Celsius
System.out.print("Enter a temperature in Celsius: ");
double celsius = input.nextDouble();
// Convert it to Fahrenheit
double fahrenheit = (9.0 / 5) * celsius + 32;
// Display the result
System.out.println(celsius + " Celsius is " +
fahrenheit + " Fahrenheit");
}}
Output:
Exercise 2
2.2 (Compute the area and volume of a cylinder) Write
a program that reads in the radius and length of a
cylinder and computes the area and volume using the
following formulas:
area = radius * radius * π
volume = area * length
Source code:
import java.util.Scanner;
public class Exercise2_2 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
// Enter radius and length of the cylinder
System.out.print("Enter the radius and length of a
cylinder: ");
double Cradius = input.nextDouble();
double Clength = input.nextDouble();
7
Source code:
double area = Cradius * Cradius * 3.14;
double volume = area * Clength;
System.out.println("The area is " + area);
System.out.println("The volume is " + volume);
}
}
Output:
Exercise 3
2.6 (Sum the digits in an integer) Write a program that
reads an integer between 100 and 999 and adds all the
digits in the integer. For example, if an integer is 932, the
sum of all its digits is 14.
Hint: Use the % operator to extract digits, and use the /
operator to remove the extracted digit. For instance, 932
% 10 = 2 and 932 / 10 = 93.
Source code:
import java.util.Scanner;
public class Exercise2_6 {
// Main method
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
// Read a number
System.out.print("Enter an integer between
100 and 999: ");
int number = input.nextInt();
11
Source code:
// Find all digits in number
int lastDigit = number % 10;
int remainingNumber = number / 10;
int secondLastDigit = remainingNumber % 10;
remainingNumber = remainingNumber / 10;
int thirdLastDigit = remainingNumber % 10;
12
Source code:
// Obtain the reverse number
int sum = (lastDigit) + (secondLastDigit) + thirdLastDigit;
// Display results
System.out.println("The sum of the digits is: "+ sum);
}
}
Output: