Example 11.19An Unambiguous Expression GrammarConsider again the language Expr, which we defined with the following context-free grammar G=({E, id, +, *, (, )},{id, +, *, (, )}, R, E), where:R={E→E+EE EEE→ (E)Eid}.G is ambiguous in two ways:1.2.It fails to specify associativity. So, for example, there are two parses for the string id+id+ id, correspondingto the bracketings (id+id) + id and id+(id+id).It fails to define a precedence hierarchy for the operators + and *. So, for example, there are two parses for thestring id + id * id, corresponding to the bracketings (id+id) * id and id+(id * id). 8) Consider the unambiguous expression grammar G' of Example 11.19.a)Trace the derivation of the string id+id*id*id in G'.b) Add exponentiation (**) and unary minus (-) to Gʻ, assigning the highest precedence to unary minus, followedby exponentiation, multiplication, and addition, in that order.

The given problem deals with context-free grammars (CFGs) and their ambiguity, specifically focusing…

8) Consider the unambiguous expression grammar G' of Example 11.19. a) Trace the derivation of the string id+id*id*id in G'. b) Add exponentiation (**) and unary minus (-) to G', assigning the highest precedence to unary minus, followed by exponentiation, multiplication, and addition, in that order.

8) Consider the unambiguous expression grammar G' of Example 11.19. a) Trace the derivation of the string id+ididid in G'. b) Add exponentiation (**) and unary minus (-) to G', assigning the highest precedence to unary minus, followed by exponentiation, multiplication, and addition, in that order.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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