10. Consider a language of expressions with only the variables a, b, and c and formed using the binary infix operators +, -, *, 7, and ↑ (for exponentiation) where ↑ has the highest precedence, * and / have the same next lower precedence, and + and - have the lowest precedence. ↑ is to be right associative and the other operations are to be left associative. Parenthe- ses may be used to override these rules. Provide a BNF specification of this language of expressions. Add attributes to your BNF specification so that the following (unusual) conditions are satisfied by every valid expression accepted by the attribute grammar: a) The maximum depth of parenthesis nesting is three. b) No valid expression has more than eight applications of operators. c) If an expression has more divisions than multiplications, then sub- tractions are forbidden.

10. Consider a language of expressions with only the variables a, b, and c and formed using the binary infix operators +, -, , 7, and ↑ (for exponentiation) where ↑ has the highest precedence, and / have the same next lower precedence, and + and - have the lowest precedence. ↑ is to be right associative and the other operations are to be left associative. Parenthe- ses may be used to override these rules. Provide a BNF specification of this language of expressions. Add attributes to your BNF specification so that the following (unusual) conditions are satisfied by every valid expression accepted by the attribute grammar: a) The maximum depth of parenthesis nesting is three. b) No valid expression has more than eight applications of operators. c) If an expression has more divisions than multiplications, then sub- tractions are forbidden.

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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