Compiler Design

Homework Assignment 2 (10 points)

Due October 12, 2004

Consider a language defined by the following syntax:

- Any integer constant is an expression
- If
*e1*and*e2*are expressions, then so are:- +++
*e1* -
*e1*--- -
*e1*+--*e2* -
*e1*--+*e2* -
*e1*++-*e2* -
*e1*-++*e2* - (
*e1*)

- +++
- Nothing else is an expression

Answer the following questions:

- [2] Write a context-free grammar for the language using only one nonterminal.
- [1] Is your grammar ambiguous? Explain your answer.
- [3] Update your grammar to make a grammar that accounting for
the following precedence/associativity information. Operators in
order of precedence from highest to lowest are (two operators at
the same bullet have highest precedence):
- +--, --+ (right associative)
- ++-, -++ (left associative)
- --- (left associative)
- +++ (right associative)

- [1] Show a right-most derivation and corresponding parse tree for +++ 5 --+ 3 +-- 4 ++- 6 +-- 2 ---
- [3] Determine the first and follow sets for your grammar. Using your sets construct a parse table for a predictive parser.