The Gateway to Computer Science Excellence

+1 vote

Hi, I am having a doubt understanding the result of CFL – Regular:

Here’s my approach:

- CFL – Regular = CFL INTERSECTION Regular’ = CFL INTERSECTION Regular = CFL
- Suppose some CFL L1= {a^n b^n | n>=1} and some Regular R1= (a+b)* :

Now if I do CFL – Reg = {ab,aabb,aaabbb, ….} – { epsilon, a, b, ab, aabb, aaabbb, …..}

It gives { phi } which is Regular (hence also CFL)

So is it better to say CFL – Regular = Regular or CFL – Regular = CFL ? If both are separate options, which one should I go for? Thanks

- All categories
- General Aptitude 1.9k
- Engineering Mathematics 7.4k
- Digital Logic 2.9k
- Programming and DS 4.9k
- Algorithms 4.3k
- Theory of Computation 6.2k
- Compiler Design 2.1k
- Databases 4.1k
- CO and Architecture 3.4k
- Computer Networks 4.1k
- Non GATE 1.4k
- Others 1.7k
- Admissions 595
- Exam Queries 576
- Tier 1 Placement Questions 23
- Job Queries 72
- Projects 17

50,654 questions

56,169 answers

193,881 comments

94,303 users