1, integer variables can be divided into the following four categories:

(1) short integer with short[int] as the type keyword.

(2) Basic integer, with type keyword of int.

(3) Long integer with long[int] as type key word.

(4) Unsigned integer, the type keyword is unsigned[int] or unsignedshort or unsignedlong.

Unsigned[int] stands for unsigned basic integer;

Unsignedshort stands for unsigned short integer;

Unsignedlong stands for unsigned long integer.

Unsigned integers can only be used to store unsigned integers.

2. Number of bytes occupied in memory and range

The number of bytes of memory occupied by integer variables of the above types varies from system to system. Generally, a machine word is used to store an int type data. The number of bytes of long type data should not be less than that of int type, and the short type should not be longer than that of int type.

On 16.

In an operating system (such as DOS), generally 2 bytes are used to store an int data; In a 32-bit operating system (such as Win-dows98), the default value is 4 bytes.