Modified testcurs.c

I've added a few comments to testcurs.c.

Thank you!
							Lawrence R. Amlord
							   Mar. 26, 2013
							   Xi'an, China
Added Exercise_3.1.

Included are the following 2 files:

	Exercise_3.1.pdf
	Exercise_3.1.tm

Here I builded the C source code into TeXmacs files, so that the solution
might seems more concise.

Thank you!
							Lawrence R. Amlord
							   Mar. 26, 2013
							   Xi'an, China
Added Exercise_3.2.

Included are the following 2 files:

	Exercise_3.2/Exercise_3.2.pdf
	Exercise_3.2/Exercise_3.2.tm

Here my solution to Exercise 3.2 may be not so perfect, but it is better than
none. There are still possibilities to improve the efficiency of the procedure
here. If you got it, please tell me!

Thank you!
							Lawrence R. Amlord
							   Mar. 26, 2013
							   Xi'an, China