Context Free Grammars
Context free grammar is a language used to retrieve strings in a given language.
Four tuples that are used to define context free grammar are:
G = (V, T, P, S)
Where:
G describes the grammar.
T describes the finite set of terminal symbols.
V describes a finite set of non-terminal symbols
P describes a set of production rules
S is the start symbol.
The derivation of the string starts from the start symbol. We can place a non-terminal repeatedly to derive the string using right-hand production.
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