Learn Ambiguous grammar, Derivation Tree, Parse tree
16 February, 2016
Ambiguous grammar: A sentence generated by a grammar is ambiguous if there exists more than one tree for it . Consider a string y= 3+7*9 of L(G) then more than one tree can be created as follows if the given grammar is
G= {N,T,P,S},N = {E}
T={+,*,(,),id}[terminals]
P=(E,A)[non-terminals]
See the below image:
- A derivation in which the rightmost non-terminals is replaced first is called to be right most derivations.
- A parse tree is a graphical representation of the steps in parsing.
- A grammar that produces more than one parse tree is said to be ambiguious grammar.
- To make a parsing of a grammar language we have to eliminate ambiguity , removing left recursion and need left factoring .
Continue in next chapter..
