Pumping Lemma

By : Manglika Tripathi

Updated : Feb 25, 2021, 4:45

Pumping Lemma is only a means to show that the given language is non-regular and not context-free. However, we cannot say that if a language satisfies Pumping Lemma, it is necessarily a regular language or context-free language. You can always refer to Pumping Lemma study material for GATE CS. BYJU'S Exam Prep offers quick access to Pumping Lemma GATE questions and answers pdf to get a brief understanding of the type of questions asked in GATE, ISRO, IES, JEE exams.

Important Pumping Lemma Topics for GATE CS



Pumping Lemma for Regular language

If L is a regular language that has a string w. Then there will be a constant c such that,


Also, w can be rewritten as xyz




xyizis part of L when i0

Pumping Lemma for Context-Free language

If L is a context-free language that has a string w, then there will be a pumping length p such that,

Length of wp

Also, w can be rewritten as



vy and

uvixyiz belongs to the string L where i0

Tips to Prepare for Pumping Lemma for GATE

  • For this, you need to go through the Pumping Lemma syllabus for GATE to understand the pattern of questions that need to be taken care of.
  • You also have to read the Pumping Lemma book to understand the concepts and numerical associated with it.
  • Also, remember that even if a string satisfies Pumping Lemma's condition, it is not necessarily regular. However, we can prove that if it doesn't fulfil the condition, it is not regular. The same rule holds for Context-free language too.
  • It would help if you went through the Pumping Lemma GATE questions to understand the topic's weightage in exams.
  • You should attempt the Pumping Lemma Online test offered by BYJU'S Exam Prep to speed up your timings.
  • Also, practice is the only key to success. So the more problems and questions you will attempt, the better your results will get.

Importance of Pumping Lemma in GATE CS Exam

  • We find that Pumping Lemma MCQ questions come for nearly 5-10 marks in exams if we look at the previous papers.
  • MCQ types of questions are usually asked, making it a scoring subject for GATE aspirants.
  • With an in-depth understanding of the topics with examples given in Pumping Lemma GATE notes, you will quickly answer the questions.
  • As these are MCQ-based questions, it will take less time and spare time to concentrate on more challenging problems.

Most Recommended Books for Pimping Lemma for GATE

Book Name


Introduction to the Theory of Computation

Michael Sipser

Theory of Computer Science

K. L. P. Mishra &

N Chandrasekaran

An introduction to Formal Languages and Automata

Peter Liz

Why Prepare Pumping Lemma from BYJU'S Exam Prep?

BYJU'S Exam Prep is a popular platform that offers in-depth training for various competitive exams. The Pumping Lemma notes for GATE pdf is curated after thorough research of previous papers covering all important concepts with a detailed example. You will also get to take Pumping Lemma online quiz to work on your speed, which will ultimately improve your performance. It would help if you also referred to their Pumping Lemma MCQ pdf to get an idea of different questions. You will also have a revision plan curated by them to keep your progress on track.BYJU'S Exam Prep offers LIVE online classes giving attention to every student at an unbeatable fee where you can get your doubts clarified in real time.

Frequently Asked Questions

Q. What is an important topic that we must study for the GATE CS exam?

You must study Pumping Lemma for computer science as it has a weightage of 5-10 marks in GATE exams. It is among top-scoring topics for the GATE exams.

Q. I am a little slow in solving numerical problems. Can you suggest a way to improve my speed?

To speed up, you would need to take the Pumping Lemma Quiz by BYJU'S Exam Prep. Also, there is no restriction on quizzes that you might attempt. It will improve your speed and accuracy too.

Q. How to prepare for the Pumping Lemma topic in the GATE exams?

It would help if you first referred to Pumping Lemma notes for CS provided by BYJU'S Exam Prep, to begin with, your preparation. All the Pumping Lemma topics for GATE CS are covered in the notes with brief explanations and examples.

Q. How many months of rigorous preparation is needed for GATE CS exams?

You need at least 3-6 months of day and night preparation. Also, this preparation needs to take place under vigilant guidance for better result

Q. How will I understand the weightage of each topic in GATE CS?

Firstly understand the Pumping Lemma GATE syllabus. Then do a thorough study of the previous year's GATE papers. It will help you in coming up with weightage for each topic.