If all the production rules have single non - terminal symbol on the left side, the grammar defined is :
context free grammar
A grammar whose every production has the form \(A \to \alpha\), with a single non-terminal A on the left, can rewrite A regardless of its surroundings.
Such grammars are the context free (Type 2) grammars; context sensitive and unrestricted grammars allow strings of symbols on the left side.
Hence, context free grammar.
The following Context-Free Grammar (CFG) :
S → aB | bA
A → a | as | bAA
B → b | bs | aBB
will generate
The context free grammar given by
\(S \to XYX\)
\(X \to aX \mid bX \mid \lambda\)
\(Y \to bbb\)
generates the language which is defined by regular expression :
A context free grammar for \(L = \{ w \mid n_{0}(w) \gt n_{1}(w) \}\) is given by :
Match the following :
| List - I | List - II |
| a. Chomsky Normal form | i. \(S \to b\,S\,S \mid a\,S \mid c\) |
| b. Greibach Normal form | ii. \(S \to a\,S\,b \mid ab\) |
| c. S-grammar | iii. \(S \to AS \mid a\) \(A \to SA \mid b\) |
| d. LL grammar | iv. \(S \to a\,B\,S\,B\) \(B \to b\) |
The context free grammar for the language \(L = \{a^{n}b^{m}c^{k} \mid k = |n - m|, n \geq 0, m \geq 0, k \geq 0\}\) is
For the above specified passage, which of the following represent the grammar for the language accepted the machine?
Which of the folowing CFG(s) is/are in chomsky Normal form (All capital letters are variables & lower case are terminals)
A. S → ABC / AB
A → a
B → b
C → d
B. X → RT / TR
T → t
R → XT / r
C. P → qP / sQ
Q → r / s
D. M → MN / MP
N → nm / n
P → p
Choose the correct answer from the options given below:
Let G = (V, T, S, P) be a context-free grammar such that every one of its productions is of the form A → v, with |v| = K > 1. The derivation tree for any W ∈ L(G) has a height h such that
| A | S $\rightarrow$ Ab aS$\rightarrow$ aA A$\rightarrow$ a | B | S $\rightarrow$ Ab A $\rightarrow$ Sa A $\rightarrow$ a |
| C | S $\rightarrow$ AS S $\rightarrow$ aA A$\rightarrow$ a | D | S $\rightarrow$ Ab S $\rightarrow$ aA A$\rightarrow$ a |
| E | S $\rightarrow$ Sb A $\rightarrow$ Aa A $\rightarrow$ $\varepsilon$ |
Which of the following grammars is (are)ambiguous ?
(1) S → SS | aSb | bSa |e
(2) S → aSbS | bSaS |e
(3) S → aAB
A → bBb
B → A Ι e
Consider the grammar,
G = S → abScB | e,
B→ bB | b.
What is the language generated by the given grammar ?
Consider the given grammar
S → Abc | ad
A → eS | Cr| ξ
C → f/p/ξ
Compute FIRST (A)
Select the sentence which is meaningful and grammatically correct.