sample question of c++ 3

                                                                                    Due Date: Nov 25^th 2011      

Course: Programming Fundamentals                                                                     Total Marks: 20

                                                                          

Problem 1:                                                                                                                                        (5 points)

Implement a function that takes a number as input from console and returns whether the number is prime or not (it returns 1 if the number is prime and 0 if the number is not prime). Following is function prototype:

int isprime(int);

Write a program that prompts the user to input two numbers. The program calculates the average of prime numbers between these numbers and displays it in the format shown below. The program uses the function isprime included as a header file. Use only what we have learned so far in the class.

Hint: 2 is the first prime number. Please make sure that you take care of this in your program.

Sample Output

Enter first number: 1 Enter second number: 20 The average of prime numbers between 1 and 20 is 9.62

Problem 2:                                                                                                                                        (5 points)

Write a program that prompts the user to input a number. The program determines and prints twin primes till that number in the format shown below. The program uses the function isprime included as a header file. Use only what we have learned so far in the class.

Hint: A pair of prime numbers that differ by 2 (successive odd numbers that are both Prime numbers) is called twin primes. e.g., (3, 5), (5, 7), (11, 13),…

Sample Output

Enter the upper limit: 100 The twin primes from 1 till 100 are: 3, 5 5, 7 11, 13 17, 19 29, 31 41, 43 59, 61 71, 73

Problem 3:                                                                                                                                      (10 points)

Implement another function which takes a number as an argument and prints it as a product of prime numbers. The prototype of the function is:

            void productofprimes(int);

The function productofprimes calls the function isprime to determine the next prime numbers.

Write a program that reads a number from console and prints it as the product of prime numbers. The program uses isprime and productofprimes functions included as a header file. Use only what we have learned so far in the class.

e.g., 90 = 2 x3 x 3 x5

       100 = 2 x 2 x 2 x 5 x 5

Sample Output

Enter a number: 200 200  expressed as product of prime numbers is: 2 x 2 x 2 x 5 x 5

Sample Output

Enter a number: 19 19  expressed as product of prime numbers is: 19

Submission Guidelines:

-          No Late Submissions will be entertained

-          Copied Assignments will be marked Zero.