Question

1. Assume the following rules of associativity and precedence for expressions:

Precedence           Highest                 *, /, not
                              + , - , &, mod
                              - (unary)
                              = , / = , 6 , 6 = , 7 = , 7
                              and
Lowest                              or, xor
Associativity         Left to right

Assume the only operands are the names a,b,c,d, and e. Write a BNF description of the precedence and associativity rules defined for such expressions.

Answer 1

Assume the following rules of associativity and precedence for expressions:

Precedence-

Highest:

*,/, not

+ , - , &, mod

-(unary)

=,/=,<,<=, >=, >

and

Lowest:

or, xor

Associativity-

Left to right

Show the order of evaluation of the following expressions by parenthe sizing all subexpressions and placing a superscript on the right parenthesis sis to indicate order. For example, for the expression

a + b * c + d

the order of evaluation would be represented as

((a + (b * c)')? + d)