What is need for nondeterministic finite automata? What is the deference between nfa and dfa?
Answers
Answer:
Step-by-step explanation:
DFA Vs NFA
Given below is a comparison chart explaining DFA vs NFA in a tabulated form based on specific differences.
Basis of Difference DFA NFA
Reaction to symbols For each symbolic representation of the alphabet, only a singular state transition can be attained in DFA. No specifications are needed from the user with respect to how certain symbols impact the NFA.
Empty string transition DFA is not capable of using an Empty String transition. NFA can use empty String transition.
Structure DA can be best described and understood as one machine. NFA is like multiple small machines that are performing computational activities at the same time.
Rejection of string DFA rejects the string in case it terminates in a state that is different from the accepting state. NFA rejects the string in the event of all branches dying or refusing the string.
Backtracking It is possible to use backtracking in DFA. It is not possible to use backtracking at all times in case of NFA.
Ease of construction Given its complex nature, it is tougher to construct DFA. NFA is more easily constructed in comparison to DFA.
Supremacy All DFAs are derived from NFAs. All NFAs are not DFAs.
Transition functions The number related to the next state is one. The number related to the next state/ states is either zero or one.
Complexities of time The total time required for running any input string in DFA is less than what it is in NFA. The total time required for running any input string in NFA is larger than that in comparison to DFA.
Full form The full form of DFA is Deterministic Finite Automata. The full form of NFA is Nondeterministic Finite Automata (NFA).
Space requirement More space allocation needed. Less space needed.
The setting of next possible set The next possible state is clearly set in DFA. In NFA, every single pair of input symbol and state may contain many possible next states.