The && (logical AND) operator indicates whether both operands are true.
If both operands have nonzero values, the result has the
value 1. Otherwise, the result has the value 0.
The type of the result is int. Both operands must
have a arithmetic or pointer type. The usual arithmetic conversions
on each operand are performed.
If both operands have
values of true, the result has the value true.
Otherwise, the result has the value false. Both operands
are implicitly converted to bool and the result type
is bool.
Unlike the & (bitwise AND) operator, the && operator guarantees left-to-right evaluation of the operands. If the left operand evaluates to 0 (or false), the right operand is not evaluated.
The following examples show how the expressions that contain the logical AND operator are evaluated:
| Expression | Result |
|---|---|
| 1 && 0 | false or 0 |
| 1 && 4 | true or 1 |
| 0 && 0 | false or 0 |
(y != 0) && (x / y)
The expression x / y is not evaluated when y != 0 evaluates to 0 (or false).
1 && 4 evaluates to 1 (or true)
while
1 & 4 evaluates to 0