# DFA / RE

- Construct a regular expression and correspondingly an FA for all words in which a appears tripled, if at

all. - Construct a regular expression and correspondingly an FA for all strings that end in a double letter. Solution
- The language of strings, defined over Σ={a, b}, beginning with b Solution
- The language of strings, defined over Σ={a, b}, not beginning with a Solution
- Language of Strings of length two or more, defined over Σ = {a, b}, beginning with and ending in different letters. Solution
- Construct a regular expression and correspondingly an FA for all strings that end in a double letter. Solution
- What language (or set of strings) is accepted by the following DFA? Solution

- Give a Regular Expression and DFA for:

L = {x ∈ {0, 1}∗ | x ends with 1 and does not contain the substring 00} Solution - Give a RE for:
*L*=*{*0*i*1*j**|**i*is even and*j*is odd*} Solution*

# NFA

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