Logical Operators

We say any expression that evaluates to zero is a FALSE logic condition and that evaluating to non-zero value is a TRUE condition. Logical operators are useful in combining one or more conditions. The following are the logical operators :

                &&         AND

                ||           OR

                !              NOT

The first two operators are binary, while the exclamation(!) is a unary operator. It is used to negate the condition.

e.g.

                x<0 && y>10      evaluates to true if both conditions are

true

                x < 0 || z = = 0   evaluates to true, if one of the

conditions is true

                !(x == 0)                                               evaluates to true if condition is false.

The unary negation operator (!) has a higher precedence amongst the these, followed by the and (&&) operator and then the or(||) operator, and are evaluated from left to right.