CONSTANTS AND LITERALS

CONSTANTS AND LITERALS

Constants refer to fixed values that the program may not alter during its
execution. These fixed values are also called literals.
Constants can be of any of the basic data types like an integer constant, a
floating constant, a character constant, or a string literal. There are enumeration
constants as well.
Constants are treated just like regular variables except that their values cannot
be modified after their definition.

IntegerLiterals

An integer literal can be a decimal, octal, or hexadecimal constant. A prefix
specifies the base or radix: 0x or 0X for hexadecimal, 0 for octal, and nothing for
decimal.
An integer literal can also have a suffix that is a combination of U and L, for
unsigned and long, respectively. The suffix can be uppercase or lowercase and
can be in any order.
Here are some examples of integer literals:

212                  /* Legal */ 215u                /* Legal */ 0xFeeL           /* Legal */ 078                 /* Illegal: 8 is not an octal digit */ 032UU           /* Illegal: cannot repeat a suffix */

Following are other examples of various types of integer literals:

85                    /* decimal */ 0213                /* octal */ 0x4b               /* hexadecimal */ 30                    /* int */ 30u                 /* unsigned int */ 30l                  /* long */ 30ul                /* unsigned long */

7. CONSTANTS AND LITERALS