## Conversion of Epsilon-NFA to NFA

Non-deterministic Finite Automata (NFA) is a finite automata having zero, one or more than one moves from a given state on a given input symbol.… Read More »

## Program to build a DFA to accept strings that start and end with same character

Given a string consisting of characters a and b, check if the string starts and ends with the same character or not. If it does,… Read More »

## Program to build a DFA that accepts strings starting and ending with different character

Prerequisite: Deterministic Finite Automata Given a string str consists of characters ‘a’ & ‘b’. The task is to check whether string str starts and ends… Read More »

## Closure properties of Regular languages

Closure properties on regular languages are defined as certain operations on regular language which are guaranteed to produce regular language. Closure refers to some operation… Read More »

## Difference between Pushdown Automata and Finite Automata

Pushdown Automata: A Pushdown automata (PDA) is a finite state machine with an added stack storage. Additional stack is used in making the decision for… Read More »

## Determining Countability in TOC

Countable Set is a set having cardinality same as that of some subset of N the set of natural numbers . A countable set is… Read More »

## Removing Direct and Indirect Left Recursion in a Grammar

Prerequisite – Classification of Context Free Grammars, Ambiguity and Parsers Left Recursion: Grammar of the form, S –> S / a / b It is… Read More »

## Total Recursive Functions and Partial Recursive Functions in Automata

Total Recursive Functions: A recursive function is called total recursive function if it is defined for its all arguments.Let f(a1, a2, …an) be a function… Read More »

## Variation of Turing Machine

Prerequisite – Turing Machine 1. Multiple track Turing Machine: A k-tack Turing machine(for some k>0) has k-tracks and one R/W head that reads and writes… Read More »

## DFA (Recognizer) for valid Pascal identifiers

Problem – Implement a recognizer for pascal identifiers based on a DFA that accepts strings belonging to the definition of the language of the same.… Read More »

## Multitape Nondeterministic Turing Machine simulator

This article tackles both theoretical and practical issues in Computer Science (CS). It reviews Turing Machines (TMs), a fundamental class of automata and presents a… Read More »

## NFA machines accepting all strings that ends or not ends with substring ‘ab’

Prerequisite: Finite Automata Introduction Problem-1: Construction of a minimal NFA accepting a set of strings over {a, b} in which each string of the language… Read More »

## Construct a DFA which accept the language L = {w | w ∈ {a,b}* and Na(w) mod 3 = Nb (w) mod 3}

Problem: Construct a deterministic finite automata (DFA) for accepting the language L = {w | w ∈ {a,b}* and Na(w) mod 3 = Nb (w)… Read More »

## Construct a DFA which accept the language L = {anbm | n > =1, (m) mod 3 = 1}

Problem: Construct a DFA which accept the language L = {anbm | n > =1, (m) mod 3 = 1}. Explanation: For constructing the DFA,… Read More »

## NPDA for accepting the language L = {wwR | w ∈ (a,b)*}

Prerequisite – Pushdown Automata, Pushdown Automata Acceptance by Final State Problem: Design a non deterministic PDA for accepting the language L = {wwR w ∈… Read More »