Question

Write a java program that demonstrates recursion. This program can be in a java GUI frame or as a console application. On this one it is up to you. (It would probably work better as a console program for this particular program.)

The input for this program is a number of boxes. Ask the user for this with a textbox or a prompt on the command line.

Demonstrate recursion with a function called LoadTruck() that takes a number of boxes to be packed as a parameter. This function should print “Truck Loaded” and subtract 5 from the number of boxes and recursively call itself until there are less than 5 boxes. That time through it should print “There are not enough to pack another truck.”

(If you wish to use a GUI, it might be best to “print” the lines by concatenating them onto the text in a textArea along with a newline character. There may be other ways you can think of to do this in a GUI using other controls. Anyway you display the trucks loaded is fine.)

This program must have a recursive method. If you use a loop to load the trucks it will not count for any of the points for this one. This lab is to demonstrate recursion.

Example of output for 23 boxes:

“Truck Loaded”

“Truck Loaded”

“Truck Loaded”

“Truck Loaded”

“There are not enough to pack another truck.”

Answer 1

package recursion;

import java.util.Scanner;

// Defines a class TruckLoaded

public class TruckLoaded

{

// Defines a recursive method to load pack to truck

void loadTruck(int numberOfBoxes)

{

// Checks if number of boxes is less than 5

// then display the message and stop the program

if(numberOfBoxes < 5)

{

System.out.println("There are not enough to pack another truck.");

System.exit(0);

}// End of if condition

// Otherwise more than 5 boxes available

else

{

// Display the message

System.out.println("Truck Loaded");

// Recursively calls the method with deducting 5 as parameter

loadTruck(numberOfBoxes -= 5);

}// End of else

}// End of method

// main method definition

public static void main(String[] args)

{

// Scanner class object created

Scanner sc = new Scanner(System.in);

// Accepts number of boxes from the user

System.out.print("\n Enter number of boxes: ");

int numberOfBoxes = sc.nextInt();

// Calls the method using anonymous object of the class

new TruckLoaded().loadTruck(numberOfBoxes);

}// End of main method

}// End of class

Sample Output 1:

Enter number of boxes: 23
Truck Loaded
Truck Loaded
Truck Loaded
Truck Loaded
There are not enough to pack another truck.

Sample Output 2:

Enter number of boxes: 32
Truck Loaded
Truck Loaded
Truck Loaded
Truck Loaded
Truck Loaded
Truck Loaded
There are not enough to pack another truck.