This homework is due Tuesday February 12 at 11:59 pm. No late homeworks will be accepted.


1. A twin prime is a prime number that is exactly two larger than the largest prime number that is smaller than it. For
example, 7 is a twin prime because it is exactly two larger than 5.  But 17 is not a twin prime because the largest
prime less than 17 is 13.

Write a program that asks the user how many twin primes the user wants to find, reads in that goal, and 
then successively examines 
the numbers starting at 2 to see if the number is a twin prime. The program stops when the specified number of
twin primes has been found. It then prints out information, as you will see in the executable version of
the solution. The executable can be executed on a csif machine by typing

~gusfield/cs30w08/twinprimes

Your program should produce EXACTLY the same output as the above program.
Name your source code twinprimes.c and use handin as follows "handin cs30a p4 twinprimes.c" to send your
file twinprimes.c to account cs30a directory p4. 
Do not send a scriptfile (the output is too large).
Remember that when you compile your source code to create executable code,
do NOT name your executable file twinprims.c.  Also, do not send in your executable file, only the source
code twinprimes.c

2.  Write a program that asks the user to write several lines of text, each ending with the return key. 
After each time the return key is pressed,
the program processes what was typed (since the last time return was entered), and replaces any 
two or more consecutive blanks with only a single
blank, printing out the prettier line. For example, if the user enters:
This     line has        many   large gaps   in    it.
the program would write out:
This line has many large gaps in it.


When the user enters the EOF key (cntrl-d for example), the program ends.

Name your source code prettyline.c.  Use handin to submit your source code prettyline.c to cs30a p4 as follows 
"handin cs30a p4 prettyline.c". You may also handin
a scriptfile, called prettyscript, if you wish, to show your program working on lines you make up and type in.

The executable can be executed on a csif machine by typing

~gusfield/cs30w08/prettyline