ONLY NEED #4

1. Regular Expression For strings containing the letters 'a' and 'b' give a regular expression that captures all strings w such that for at least one of the two letters, the number of times that letter appears is even (E.., ababa, bbb are in the language, while ba, aaab are not). 2. NFA Give a non-deterministic finite automaton that captures the regular expression from above. Show the automaton in graphical form. 3. DFA Using the construction described in class, give a deterministic version of the automaton. You only need to show the transition table. 4. Minimization Give a minimized version of the finite automaton, using the algorithm we used in class. You only need to show the state transition diagram