#define Preprocessing Directive: Symbolic Constants
#define preprocessing directive creates symbolic constants—constants represented as symbols—and macros—operations defined as symbols. The
#define preprocessing directive format is
#define identifier replacement-text
When this line appears in a file, all subsequent occurrences (except those inside a string) of identifier in that file will be replaced by replacement-text before the program is compiled. For example,
#define PI 3.14159
replaces all subsequent occurrences of the symbolic constant
PI with the numeric constant
3.14159. Symbolic constants enable you to create a name for a constant and use the name throughout the program. Later, if the constant needs to be modified throughout ...
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