The - arithmetic operator designates a subtraction operation, or to indicate a negative numeric value.

num.exp-num.exp

Subtracts 1 from the contents of variable x.

x = x - 1

Negates the contents of z and adds to the contents of x. The result is placed in x.

x = x + (-z)

Subtracts the contents of the variable discount.amount from the variable price. Places the result in the variable amount.

amount = price - discount.amount

Subtracts the contents of variable discount.amount from the product of unit.cost and qty. The () are used to group precedence are unnecessary due to default precedence. They are added for program clarity.

amount = (unit.cost * qty) - discount.amount

This assigns the value, -1, to the variable counter.

counter = -1

*= assignment operator, + arithmetic operator, += assignment operator, -= assignment operator, /= assignment operator, := assignment operator, Arithmetic expressions, Arithmetic operators, Numeric expressions, Precedence, precision statement, Relational operators, Reserved characters, \= assignment operator