An Int type of data occupies 4 bytes, with 8 bits each and ***32 bits. Therefore, the maximum storage capacity is 365438+2 to the power of 0 (starting from the power of 2). But the first bit of 32 bits is the sign bit, so the power of 2 is 3 1 minus 1. Simply put, the Int type occupies 4 bytes, so this is the value range.

Short, int, long, char, float and double represent six basic data types in C language.

Naming rules:

1, which must consist of alphanumeric characters, underscores and dollar symbols.

2. It can't start with a number.

3. Some identifiers are used by the system, so when defining identifiers, they cannot be duplicated with system identifiers (keywords).

4. Understand 32 keywords in C language.