Homework 3:
Multithreaded factoring with performance benchmark

Input:
arg0, 1, 2, and 3 will each be a long (64bit integer)
arg4 will be an int that determines the number of threads you use


output:
1. A sorted list of the factors of arg0 (naive approach without threads)
2. The time in milliseconds that it took to calculate output 1
3. A sorted list of the factors of arg0 (multi-threaded approach use X threads where X = arg4)
4. The time in milliseconds that the multi-threaded approach took
5. Lists of the factors of arg1, arg2, arg3 (multi-threaded approach, print each number and then its factors so it is clear which go with each number)
6. The factors that arg1, arg2, and arg3 all have together in common
7. The number of Factors objects created in total (see Factors class below)
NOTE: for full credit in 7 use a static attribute and method in the Factors class to track and print

NOTE: For full credit create another class called Factors in addition to your runnable class. Factors should have:
0. An attribute that holds the factors of a number (Some type of set or array most likely)
1. A constructor that takes a long (number to find factors of) and an int (number of threads to use) and then spawns threads that find the factors in parallel. Add all the factors into the class's attribute to finish.
2. Another constructor that just takes an array or set to create the Class
3. A method that takes a set and/or other data structure and adds its elements all to the Factors attribute aka takes the union of the two sets (use this method in part 1 to add factors from each thread back to the class)
4. A method that prints all the factors in the class (useful for parts of the output requirement)
5. A static attribute and method that tracks and prints the total number of Factors objects created (increment the static attribute in the constructors)

NOTE: Any factoring algorithm is fine for full credit all I am looking for is a workload for multiple threads

Example input:
900000003 9 12 15 4

Example Output:
1 3 7 21 49 147 6122449 18367347 42857143 128571429 300000001 900000003
Single threaded took: 8305  (NOTE: your time will vary based on the factoring algorithm and CPU speed)
1 3 7 21 49 147 6122449 18367347 42857143 128571429 300000001 900000003
4 Threads took: 4178 (NOTE: on a multi CPU machine this should be at most half of the single threaded time if your JVM is setup to use multiple CPUs)
9: 1 3 9
12: 1 2 3 4 6 12
15: 1 3 5 15
1 3
4 (NOTE: could be 5 if you use the Factors class for the intersection as well)