Programming & Computer Science Answers

Consider a system with 14 dedicated devices of the same type. All jobs currently running on this system require a maximum of five devices to complete their execution but they each run for long periods of time with just three devices and request the remaining two only at the very end of the run.

Assume that the job stream is endless and that your operating system’s device allocation policy is a very conservative one: No job will be started unless all the required drives have been allocated to it for the entire duration of its run.

a. What is the maximum number of jobs that can be active at once?

b. What are the minimum and maximum number of devices that may be idle because of this policy?

c. Under what circumstances would an additional job be started? Explain your answer.

Develop a system by using Java programming language and object-oriented programming concepts for a hotel room reservation system. It should be a menu-driven stand-alone console application (No GUI required). No need to connect any database as well, but you may use file operations if required (not mandatory). Your system must have the following functionalities

o Register guests

o View available rooms

o Allocate a room for a guest

o Change/ delete room allocation for a guest

o Check-in to a room

o Checkout from a room

o Generate the bill

apply the following looping statement : for loop, while loop, and do while loop

Write a program that calculates and produces these two columns sequence numbers using the three looping statements:

Sequence nos. Squared

1 1

2 4

3 9

4 16

5 25

Expert's answer

Write a program to classify athletes into three classes by weight. The categories are: over 80kg → heavy weight, between 60 and 80 kg → medium weight, less than 60kg → light weight.

apply the following looping statement : for loop, while loop, and do while loop

Write a program that calculates and produces these two columns sequence numbers using the three looping statements:

Sequence nos. Squared

1 1

2 4

3 9

4 16

5 25

A perfect number is an integer that is equal to the sum of its factors. For example, 6 is a perfect number as 6 = 3+2+1. Write down a program that takes an integer x as an input and prints all perfect numbers from 1 to x.

Write a program to scan a number n and then output the sum of he powers from 1 to n.

Thus, if the input is 4, the output should be 288 because:

11 + 22 + 33 + 44 1 + 4 + 27 + 256 = 288

1st Solution – using for loop

2nd Solution – using while loop

3rd Solution-­‐ using do while loop

Create a Windows application that contains two textboxes and three buttons. One of the textboxes and one of the buttons are initially invisible. The first textbox should be used to input a password. The textbox should be masked to some character of your choosing so that the characters entered by the user are not seen on the screen. When the user clicks the first button, the second textbox and button should be displayed with a prompt asking the user to reenter his or her password. Set the focus to the second password textbox. Now, when the user clicks the second button, have the application compare the values entered to make sure they are the same. Display an appropriate message indicating whether they are the same. Once the check is made, display a third button that resets the form

Write a function called print volume (r) that takes an argument for the radius of the sphere, and prints the volume of the sphere.

•  Create a public class Student that has: o three private attributes:
• name (String)
•  an array of grades (array of integers).
• finalGrade (float) which contains the average of the grades

entered in the array

• The following public methods:
•  A constructor allowing only to initialize the name of the student.
•  A setter for the attribute name
•  A method void addGrade(int nbr) in which nbr is the size
• of the array. The method should ask the user to enter the grades and then computes the average (finalGrade) without displaying it.
•  A method String toString() that returns the a String in the following format:
• Name of the student: name Final grade: finalGrade
•  Create a test class Test in which you:
•  Create an instance of the class Student
•  Change the name of your Student instance o Invoke the addGrade(int nbr) method
•  Invoke the toString() method.