Formal Language And Its Type.finite automata and formal languages
Formal Language And Its Type.finite automata and formal languages
Contents [hide]
- 1
What is a Formal Language? - 2
Types of Formal Languages (Chomsky Hierarchy) - 3
Finite Automata (FA) - 4
Applications of Formal Languages - 5
Want a Video in Hindi? - 6
Need PDF Notes or a Short Course?- 6.1 Formal Language And Its Type.finite automata and formal languages
- 6.2 UNIT โ I โ Formal Language and Automata โ SMT1404
- 6.3 An Introduction to Formal Languages and Automata
- 6.4 FORMAL LANGUAGES AND AUTOMATA THEORY
- 6.5 DIGITAL NOTES ON FORMAL LANGUAGES AND โฆ
- 6.6 Formal Languages and Automata Theory
- 6.7 Formal Languages and Automata Theory.
Formal Language and Its Types | Finite Automata and Formal Languages
Formal language and automata theory form the mathematical foundation of computer science, especially compiler design, language processing, and artificial intelligence.
What is a Formal Language?
A formal language is a set of strings made from a finite alphabet and governed by specific syntactic rules. It is used to define and analyze languages that computers can process.
- Alphabet (ฮฃ): A finite set of symbols (e.g., ฮฃ = {0,1})
- String: A finite sequence of symbols from an alphabet
- Language (L): A set of strings over an alphabet (L โ ฮฃ*)
Types of Formal Languages (Chomsky Hierarchy)
| Language Class | Automaton / Recognizer | Grammar Type | Example Language |
|---|---|---|---|
 Regular Languages |
Finite Automata (FA) | Type 3 โ Regular | Binary numbers divisible by 3 |
 Context-Free Languages |
Pushdown Automata (PDA) | Type 2 โ CFG | Balanced parentheses ((())) |
 Context-Sensitive |
Linear Bounded Automata (LBA) | Type 1 โ CSG | a^n b^n c^n where n โฅ 1 |
 Recursively Enumerable |
Turing Machine (TM) | Type 0 โ Unrestricted | All computable languages |
Finite Automata (FA)
Used to recognize regular languages. There are two main types:
1. DFA (Deterministic Finite Automaton)
- One unique path for each input symbol
- No ฮต (epsilon) transitions
2. NFA (Non-Deterministic Finite Automaton)
- Multiple paths allowed for a single input
- Can include ฮต-transitions
Formal Definition of DFA:
DFA = (Q, ฮฃ, ฮด, q0, F)
Q = set of states
ฮฃ = input alphabet
ฮด = transition function (Q ร ฮฃ โ Q)
q0 = initial state
F = set of accepting states
Applications of Formal Languages
- Design of compilers and interpreters
- Lexical analysis using regular expressions
- Pattern matching, string searching (grep, regex)
- Natural language processing
- Design of protocols, algorithms, and AI models
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Formal Language and Automata Theory in Hindi โ Part 1
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