diff -r ca349cfe3474 -r c29853b672fb hws/hw01.tex --- a/hws/hw01.tex Sat Nov 01 15:06:41 2014 +0000 +++ b/hws/hw01.tex Sat Nov 01 16:19:05 2014 +0000 @@ -42,7 +42,9 @@ \item How is the power of a language defined? (Hint: There are two rules, one for $\_^0$ and one for $\_^{n+1}$.) -\item Let $A = \{[], [a], [b], [c]\}$. How many strings are in $A^4$? +\item Let $A = \{[a], [b], [c], [d]\}$. How many strings are in $A^4$? + Consider the case of $A^4$ where one of the strings in $A$ is the + empty string. \item How many regular expressions are there to match the string $abc$? How many if they cannot include $\epsilon$ and $\varnothing$?