2.long is short for long int, which means that in C language, long int type and long type are the same.
3. Each long occupies 4 bytes. In a 32-bit compilation system, long and int occupy the same space. This also leads to less and less use of long variables.
4. The integer range that 4.Long can represent is -2,147,483,648 ~ 2,147,483,647, that is,-2 32 ~ 2 32-1.
When used for C format input and output, the format character of long is "%ld".
5.long, like other integer types, can be combined with unsigned to form unsigned long, that is, unsigned long, and its formatting character is "%lu".
6. Under some compilers, such as gcc, two long types are used together, that is, long long type, which represents the longest system integer type in C language at present, and each long long type accounts for 8 bytes and 64 bits. Its format character is "%lld".