Datasheet

Array and Pointer types

Type Bits Min Max

unsigned long long 64 0 18446744073709551615

The following are the floating point types:

Table C.2. Floating Point Types

Type Bits Exponent Min Exponent Max

float 32 -126 127

double 32 -126 127

long double 64 -1022 1023

A number containing no decimal and not beginning with a zero is assumed to be a decimal constant of

the type int. In many contexts, however, the compiler may recognize that some other type was intended

such as unsigned or long.

A number beginning with a 0 is taken as an octal constant. In this case the digits 8 and 9 are not

permitted. A number beginning with 0x is taken as a hexadecimal constant. In this case the additional

characters a A b B c C d D e E f F are permitted.

A binary constant may be specified as a string of 1 and 0 characters preceded by 0b.

A constant may be specified as long by suffixing it with l or L. A constant may be specified as

unsigned by suffixing it with u or U.

Constants may also be represented as their ASCII equivalents when surrounded by single quotes. For

example, 0x31, 49 and '1' represent the same value.

There are a number of special strings called escape sequences that may be used to represent

special characters in ASCII constants:

• \0 - 0, the NULL character

• \a - 7, the bell character

• \b - 8, the backspace character (not the same as the backspace key)

• \t - 9, the tab character

• \n - 10, the newline character

• \v - 11, the vertical tab character

• \f - 12, the formfeed character

• \r - 13, the carriage return character

• \0 followed by octal digits - the octal value of a character

• \0x followed by hex digits - the hexadecimal value of a character

C.3.2. Array and Pointer types

Pointer types are very important in C, perhaps more important than in many languages. A pointer is a

variable that contains the address of some object.

C also allows the specification of arrays of any type, even other aggregate types, including arrays. An

issue that can be challenging at first is that the name of an array is a pointer to an array.