Consider the following two Grammars:
$G_1 \: : \: S \rightarrow SbS \mid a$
$G_2 : S \rightarrow aB \mid ab, \: A \rightarrow GAB \mid a, \: B \rightarrow ABb \mid b$
Which one of the folloeing options is correct?
- Only $G_1$ is ambiguous
- Only $G_2$ is ambiguous
- Both $G_1$ and $G_2$ are ambiguous
- Both $G_1$ and $G_2$ are not ambiguous