Question

Find a regular expression to describe: The set of all strings over the alphabet {a, b,...

  1. Find a regular expression to describe:

The set of all strings over the alphabet {a, b, c, d} that contain exactly one a and exactly one b

So, for example, the following strings are in this language:

  • ab, ba, cccbad, acbd, cabddddd, ddbdddacccc

and the following strings are NOT in this language:

a, ccbc, acbcaaacba, acacac, bcbbbbbca, aca, c, d, b

Homework Answers

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Give a regular expression for the set of all strings on the alphabet {0,1} with no...
Give a regular expression for the set of all strings on the alphabet {0,1} with no runs of length greater than 3(for example, no substrings 0^i or 1^i with i > 3)
For each of the following regular expressions, give 2 examples of strings that are in the...
For each of the following regular expressions, give 2 examples of strings that are in the language described by the regular expression, and 2 examples of strings that are not in that language. In all cases the alphabet is {a,b}. ab*ba* (a ∪ ε)b* (a ∪ b)ε*(aa ∪ bb)
Which one of the following languages over the alphabet {0,1} is described by the regular expression...
Which one of the following languages over the alphabet {0,1} is described by the regular expression (0+1)* 0 (0+1)* 0 (0+1)* ? a.The set of all strings that begin and end with either 0 or 1 b.The set of all strings containing at most two zeros c.The set of all strings containing at least two zeros. d.The set of all strings containing the substring 00
Show a regular expression representing the described set: a). The set of strings of odd length...
Show a regular expression representing the described set: a). The set of strings of odd length over {s,t,r,i,n,g} containing exactly 3 n's.
Consider a set of ? strings over alphabet ? = {?, ?}, defined recursively as follows....
Consider a set of ? strings over alphabet ? = {?, ?}, defined recursively as follows. ?∈? ? ∈ ? ⟹ ??? ∈ ? Furthermore, ? has no elements other than those obtained by finitely many applications of the recurrence rule given in its definition. For example, the first four elements of ? are ?, ???, ?????, ??????? Use mathematical induction to prove that there are no strings in ? that end in ?. {3 points.
Give a regular expression for each of the following sets: a) set of all string of...
Give a regular expression for each of the following sets: a) set of all string of 0s and 1s beginning with 0 and end with 1. b) set of all string of 0s and 1s having an odd number of 0s. d) set of all string of 0s and 1s containing at least one 0. e) set of all string of a's and b's where each a is followed by two b's. f) set of all string of 0s and...
Let A be the set of all strings of decimal digits of length five. For example...
Let A be the set of all strings of decimal digits of length five. For example 00312 and 19483 are strings in A. a. How many strings in A begin with 774? b. How many strings in A have exactly one 8? c. How many strings in A have exactly three 6’s? d. How many strings in A have the digits in a strictly increasing order? For example 02357 and 14567 are such strings, but 31482 and 12335 are not.
Q2 [10 pts] Give DFA's accepting the following languages over the alphabet {0,1}: a) The set...
Q2 [10 pts] Give DFA's accepting the following languages over the alphabet {0,1}: a) The set of all strings whose 3rd symbol from the right end is a 0. b) The set of strings such that the number of 0's is divisible by 3 and the number of 1's divisible by 2.
Are the following languages over {a, b} regular? If they are then prove it. If they...
Are the following languages over {a, b} regular? If they are then prove it. If they are not prove it with the Pumping Lemma {an bm | m != n, n >= 0} {w | w contains the substring ‘aaa’ once and only once } Clear concise details please, if the language is regular, provide a DFA/NFA along with the regular expression. Thank you. Will +1
(a) How many 12-bit strings contain exactly five 1's? (b) How many 12-bit strings contain at...
(a) How many 12-bit strings contain exactly five 1's? (b) How many 12-bit strings contain at least nine 1's? .(c) How many 12-bit strings contain at least one 1? (d) How many 12-bit strings contain at most one 1?
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT