Question 10.7.9: A regular expression is given. Construct a nondeterministic ......

This automaton is constructed inductively, following the definition of a regular expression. If the regular expression is a letter or e, the corresponding automaton has one edge. If the regular expression is Λ, the automaton has no edges at all. A union is implemented as follows: (Fig 1)

Here the picture for the union of three sets is drawn. The rectangles show the corresponding nondeterministic finite automata; their initial and final vertices are shown. New arrows (there are six of them) are unlabeled. Concatenation corresponds to the following picture: (Fig 2)

Finally, iteration corresponds to the picture (Fig 3)