Write the context-free grammars which generate the following languages: a. ?={?∈{?,?}∗ | ? is an...

Question

Question

Write the context-free grammars which generate the following languages:
a. ?={?∈{?,?}∗ | ? is an odd length string}

Answer 1

Answer #1

Regular expression for generating odd length string is (a+b)((a+b)(a+b))*

context free grammar from above regular expression is:

S->AB

A->a | b

B-> aaB | abB | baB | bbB | ε

where S,A,B are variables and a,b,ε are terminals

Answer 2

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