DFA / RE

1. Construct a regular expression and correspondingly an FA for all words in which a appears tripled, if at
   all.
2. Construct a regular expression and correspondingly an FA for all strings that end in a double letter. Solution
3. The language of strings, defined over Σ={a, b}, beginning with b Solution
4. The language of strings, defined over Σ={a, b}, not beginning with a Solution
5. Language of Strings of length two or more, defined over Σ = {a, b}, beginning with and ending in different letters. Solution
6. Construct a regular expression and correspondingly an FA for all strings that end in a double letter. Solution
7. What language (or set of strings) is accepted by the following DFA? Solution
   
8. Give a Regular Expression and DFA for:
   L = {x ∈ {0, 1}∗ | x ends with 1 and does not contain the substring 00} Solution
9. Give a RE for: L = {0i1j | i is even and j is odd } Solution

NFA

1. Give a NFA that only accepts binary numbers including the substring “101”. Solution