CSE Corner

DFA NFA It is called deterministic finite automata It is called non-deterministic finite automata For Every symbol of the alphabet, there is only one state transition in DFA. We do not need to specify how does the NFA react according to some symbol. DFA cannot use Empty String transition. NFA can use Empty String transition. DFA can be understood as ...

Here are some reasons to study automata theory in computer science . Introducation to finite automata Structural Representation Automata and Complexity Introducation to Finite Automata Finite automata are a useful model for many kinds of hardware and software. Software for designing and checking the behaviour of digital circuits The 'Lexical Analyzer' of a typical compiler, that is .. the compiler components that break the inputs text into logical units, such as: identifiers,keywords and punctuations. Software for scanning large bodi...

------------------------------------- Posted By - Nazmul Haque Nahin

Symbol The symbol is the smallest building block in the theory of computation and can be any letter, number or even pictograms. For example: a, b, 0, 1 Alphabet From the symbols we can form an alphabet represented by the sigma sign (Σ). The alphabet is nothing more than a finite set of collection of symbols. For example: Σ = {a,b}{0,1} String A string is a sequence of symbols from the alphabet. For example: Σ = {a,b} Possible strings are: String "a" of length 1 String "b" of length 1 String "aa" of length 2 String "ab" of length 2 String "aaa" of length 3 Question: How many strings of length 2 are possible over alphabet {a,b}? Answer: 4. The strings are: aa, ab, ba and bb Question: How many strings of length 2 and starting with "a" are possible over alphabet {a,b}? Answer: 2. The strings are: aa, ab Question: How many strings of length n are possible...