SKEDSOFT

Automata | Comp. Sc. Engg.

Example 2: Show that the grammar S ® S | S, S ® a is ambiguous.

Solution: In order to show that G is ambiguous, we need to find a wÎL(G), which isambiguous.

Assume w = abababa.

The two derivation trees for w = abababa is shown below in Fig. (a) and (b).