Programming & Computer Science Answers

Write a Java driven application that performs the following tasks:

1. Allow the user to decide on the length of an array that will be created at run time.

2. Enter integer elements into such an array

3. Sort the elements in ascending order (DO NOT USE bubble sort)

4. Search for a user specified element in the array and return the number of times

the searched key is observed (DO NOT USE linear search)

The students’ IDs and test answers are

stored in a file. The first entry in the file contains answers to the test in the form:

TFFTFFTTTTFFTFTFTFTT

Every other entry in the file is the student ID, followed by a blank, fol- lowed by the student’s responses. For example,

the entry:

ABC54301 TFTFTFTT TFTFTFFTTFT

indicates that the student ID is ABC54301 and the answer to question 1 is True, the answer to question 2 is False, and

so on. This student did not answer question 9. The exam has 20 questions, and the class has more than 150 students.

Each correct answer is awarded two points, each wrong answer gets one point deducted, and no answer gets zero

points.

Write a program that processes the test data. The output should be the student’s ID, followed by the answers, followed

by the test score, followed by the test grade. Assume the following grade scale: 90%–100%, A; 80%–89.99%, B; 70%–

79.99%, C; 60%–69.99%, D; and 0%–59.99%, F.

you are working as a freelancer. A company approached you and asked to create an algorithm for username validation. The company said that the username is string S .You have to determine of the username is valid according to the following rules.

1.The length of the username should be between 4 and 25 character (inclusive).

2.Valid username must start with a letter.

3 Valid username can only contain letters, numbers, and underscores characters.

4 Valid username cannot ends with the underscore character and also doesn't accept the special characters.

INPUT: The first line contains an integer T representing the number of test cases.

The first line of each test cases input contains a string.

OUTPUT: Each test case gives a Boolean value as output(true or false)

sample Input:

3

google

Google_123

google@123

sampleOutput

true

true

false

sample input 2

HelloPython

#Coder

CoderIt

sampleoutput 2

true

false

true

a runner runs 14 kılometers in 45 minutes and 30 sec-

onds. Write a program that displays the average speed in miles per hour. (Note that

 1 mile is 1.6 kilometers.)

Write a program which consists of a single class called BuyStuff that asks the user for two amounts, adds them, calculates tax at 15%, shows the result to the user, and asks for money. It then compares if the person gave enough money. If so, it displays the amount of change to return otherwise it displays a message asking for more money

Create your own class named BankAccount that illustrates the use of encapsulation as shown above.

Make sure to include at least one setter and one getter for the class. Add variables and methods

related to a BankAccount class as many as you can.

Write a program that requests the user for a year (you can assume the year will always be at

least 2000), the population of Brazil in that year (in terms of millions of people) and the annual

population growth rate (always as a real number in the range 0 – 1), and then uses the two

methods written above to determine and display the year in which Brazil’s population first

exceeded/exceeds 18

a) Write a method PopulationTotal that accepts 2 positive values, namely the current

population (in millions, e.g. a value of 1.5 means 1.5 million people) and the growth rate (e.g.

0.14 means 14%). The method determines and returns the total population based on the current

population and growth rate. For example, if the current population for a country is 1.165 million

people, and the annual population growth rate is 10%, then the total population is 1.2815 million

people after 1 year.

b) Write a method Over180Million that accepts a positive value representing the population (in

millions). The method determines whether the population is over 180 million people, and returns

a value of true if this is so, otherwise returns a value of false.