Theory of Computation

49 articles in this topic

NFA Basics and Design: Build and Trace Nondeterministic Automata

Learn how an NFA branches, trace complete state sets, handle epsilon-closure, and convert a worked three-state machine into its reachable-subset DFA.

Updated 1 Sep 20265 min readTheory of Computation

Chomsky Hierarchy Explained: Grammar Types, Worked Classification and Exam Traps

Learn how to test a grammar from Type 3 outwards, distinguish all four production classes, classify a complete grammar, and derive its strings step by step.

Updated 31 Aug 20266 min read132 viewsTheory of Computation

Turing Machine Basics and Design: Step-by-Step Worked Example for GATE

Build a deterministic single-tape TM that decides L = {0^n1^n | n >= 1}. Follow every move on 0011, test rejection cases, and connect the design to correctness and halting.

Updated 29 Aug 20266 min readTheory of Computation

Simplification of CFG: Eliminate Epsilon, Unit and Useless Productions Step by Step

Learn the safe order for simplifying a context-free grammar. One example tracks every production through epsilon removal, unit closure, and useless-symbol removal.

Updated 27 Aug 20266 min readTheory of Computation

Backus-Naur Form (BNF) Explained: Grammar Rules, Worked Derivations and Exam Traps

Learn to read BNF as a grammar, not as punctuation. Follow complete derivations, compare ambiguous parses, and see how recursion affects parsing.

Updated 26 Aug 20265 min read524 viewsTheory of Computation

Complexity Theory in Theory of Computation: P, NP, NP-Completeness and Worked Examples

Build complexity theory from input encoding upwards, then test each idea through a verified certificate and a complete 9-vertex reduction graph.

Updated 24 Aug 20266 min readTheory of Computation

Closure Properties of Regular, Context-Free and Recursive Languages for GATE: The Complete Table with MSQ Drills

Learn the closure table through the few cells that cause most mistakes, then test the logic on four solved MSQ statements.

Updated 22 Aug 20265 min readTheory of Computation

Pushdown Automata and CFG: Construction, Stack Traces and CFL Tests

Build a CFG and PDA for one language, trace both, convert the grammar, and settle the main CFL property traps with proofs.

Updated 21 Aug 20266 min readTheory of Computation

Theory of Computation for GATE: Syllabus Map, Weightage Audit and Preparation Order

Map the official Theory of Computation syllabus, audit its completed GATE 2026 paper weightage, and revise finite automata, PDA and Turing machines in dependency order.

Updated 19 Aug 20265 min read51 viewsTheory of Computation

Non-Deterministic Finite Automata (NFA): Design, Epsilon Closures and NFA-to-DFA Conversion

Learn to follow every branch of an NFA without guesswork. Two worked machines connect active-state sets, epsilon closure and a complete eight-state DFA conversion.

Updated 17 Aug 20266 min read58 viewsTheory of Computation

Regular Expressions in Theory of Computation: Rules, Conversions and Worked Examples

Learn what classical regular expressions denote, construct one from a language condition, convert it through NFA and DFA, and check equivalence with worked examples.

Updated 15 Aug 20266 min read110 viewsTheory of Computation

Moore and Mealy Machines: Output Tracing, Conversion and Worked Examples

Learn how state outputs and transition outputs change a trace. Two binary examples show parity, Moore-to-Mealy conversion and the exact state splitting needed in the reverse direction.

Updated 13 Aug 20266 min readTheory of Computation