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discrete-mathematicsfinite-automata

Constructing DFAs/NFAs What does the following notation mean: L = Σ* - λ

I am just trying to figure out what the following notation means:

L = Σ* - λ

In regards to what "- λ" signifies. I know that "λ" means empty string, but I am not sure what "-" is implying.

Context: Construct a DFA or NFA (Deterministic/Non-deterministic Finite Automata) that accepts the language above where the alphabet is {0, 1}. My guess is that it means no empty strings are allowed? No idea. Thank you for the help.

Solution

  • Σ*: All finite strings of the alphabet Σ

    λ: The empty String

    Σ* - λ: All finite strings of the alphabet Σ EXCEPT the empty string.

    Both terms are sets, and - is the set difference.