Definition: Let L be a language. L is a context-free language (CFL) if there exists a context-free grammar that generates L.
Example:
L = {anbn: n ³ 0} is a CFL.
Context-Free Language (CFL)
 Gist: A language  generated by a CFG.
G = (N, T, P, S), where N = {S}, T = {a, b},
P = {1: S ® aSb, 2: S ® e}
S Þ e       [2]
S Þ aSb [1] Þ ab         [2]
S Þ aSb [1] Þ aaSbb [1] Þ aabb [2]
Textové pole: …
…
L(G)
= {anbn: n ³ 0}
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