Computer Programming
Lecture 3
, Working with arithmetic expressions
• Basic arithmetic operators: +, -, *, /
• Precedence: one operator can have a higher priority, or precedence,
over another operator.
– Example: * has a higher precedence than +
– a+b*c
– if necessary, you can always use parentheses in an expression to force the
terms to be evaluated in any desired order.
• Associativity: Expressions containing operators of the same
precedence are evaluated either from left to right or from right to left,
depending on the operator. This is known as the associative property of
an operator
– Example: + has a left to right associativity
• In C there are many more operators -> later in this course !
• (Table A5 in Annex A of [Kochan]: full list, with precedence and
associativity for all C operators)
Lecture 3
, Working with arithmetic expressions
• Basic arithmetic operators: +, -, *, /
• Precedence: one operator can have a higher priority, or precedence,
over another operator.
– Example: * has a higher precedence than +
– a+b*c
– if necessary, you can always use parentheses in an expression to force the
terms to be evaluated in any desired order.
• Associativity: Expressions containing operators of the same
precedence are evaluated either from left to right or from right to left,
depending on the operator. This is known as the associative property of
an operator
– Example: + has a left to right associativity
• In C there are many more operators -> later in this course !
• (Table A5 in Annex A of [Kochan]: full list, with precedence and
associativity for all C operators)
