User`s manual

240 digi.com Operators
Logical NOT. This is a unary operator. Observe that C does not provide a Boolean data type. In C, logical
false is equivalent to 0. Logical true is equivalent to non-zero. The NOT operator result is 1 if the operand
is 0. The result is 0 otherwise.
test = get_input(...);
if( !test ){
...
}
13.7 Postfix Expressions
Grouping. Expressions enclosed in parentheses are performed first. Parentheses also enclose function
arguments. In the expression
a = (b + c) * 10;
the term b + c is evaluated first.
Array subscripts or dimension. All array subscripts count from 0.
int a[12]; // array dimension is 12
j = a[i]; // references the ith element
The dot operator joins structure (or union) names and subnames in a reference to a structure (or union) ele-
ment.
struct {
int x;
int y;
} coord;
m = coord.x;
!
( )
[ ]
. (dot)