Primes Project - Homework 4

Due Wednesday, October 26.

Write a program that completes the following tasks.  When you are done, email me the source code.

• Ask user to enter a positive integer (and do input validation, to make sure that the number they enter is positive)
• Print out the factors of that number
• Print out "Number is Prime" or "Number is Composite (Not Prime)"
• Use a loop to print all the prime numbers less than 100.
• Use a loop to print the first 150 prime numbers.

In your program, you can create whatever functions you feel you need.  You should at least have these two functions:

bool isPrime(int x)

int numFactors(int x)

To test your program, you might want to try these:

7759 is prime
363751127 is prime

49106711 has factors {1, 6329, 7759, 49106711}
83106649 has factors {1, 7759, 10711, 83106649}

For some of those larger numbers, you may notice that it takes a long time unless you use the shortcut we talked about in class.  Remember: you don't have to try dividing by every number from 1 up to x to determine if x is prime or not.