modified:   Makefile
	modified:   ex10
	new file:   ex11
	new file:   ex11.c
	new file:   ex12
	new file:   ex12.c
	deleted:    ex1
	deleted:    ex10
	deleted:    ex11
	deleted:    ex12
	deleted:    ex3
	deleted:    ex4
	deleted:    ex5
	deleted:    ex6
	deleted:    ex7
	deleted:    ex8
	deleted:    ex9