Question

can someone please answer these in the correct format:

Assignment #2

Total 43 pts

1. (12pts) List at least 3 words in the language and write regular expressions for the following:

1. S = {a,b,c} L = {all words that have only one letter c in them}

2. S = {a,b,c} L = {all words in which c’s appear in groups of two}

3. S = {a,b,c} L = { all words that begin and end with the same letter}

4. S = {a,b,c} L = { all words that begin and end with a different letter

2. (5pts) Write a grammar for the language S = {a,b,c} L = {all words that have only one letter c in them}

3. (5pts) Write a grammar for the language S = {a,b,c} L = {all words where every b is immediately followed by the letter c}

4. (10pts) Using the grammar below show a leftmost derivation

for A = B * (C + A)

<assign> à<id> = <expr>

<id> à A | B|C

<expr>à <expr> + <term>

                | <term>

<term> à <term> * <factor>

    |<factor>

<factor> à ( <expr> )

               |<id>

5. (5pts) Given the following grammar

Sà aScB | A | b

Aà cA | c

             Bà d | A

   Show a rightmost derivation for: acccc

6. (6pts) Is the following grammar ambiguous? Explain your answer.

S-->AB | BA

A-->AA | b

B -->Bb | a

Answer 1