Fundamentals of C language -- the data type meaning of 2-4 pointers and the analysis of forced type conversion

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The data type meaning of the pointer

A pointer involves two variables : A pointer variable itself , One is the variable pointed to by the pointer variable

int *p
p（ The pointer variable itself ） yes int * type ,*p（ The variable pointed to by the pointer ） yes int type

int * It's the pointer type , As long as the pointer type is occupied 4 Bytes , The resolution method is based on the address . All pointer types （ Whether it's int *、char *、double *） The parsing method is the same , They're all addresses .

For the variable pointed to by the pointer , The type of pointer is important . The type of the variable pointed to by the pointer （ The resolution method of its corresponding memory space ） It depends on the pointer type . If the pointer is int * Of , Then the variable pointed to by the pointer is int Type of .

Pointers and cast types

The data type meaning of variables
All types of data are stored in memory , Are stored in binary format . So there is only 0 and 1, I don't know int Type or double type .

int、char、short And so on belong to plastic surgery , Their storage was （ Convert to binary and store in memory ） It's the same , It's just that the memory grid size is different （ So these shaping formats are compatible with each other ）. and float and double The storage methods of are different from each other , And plastic surgery is even different .
It is stored according to the data type of the variable itself . But when it is taken out, it is parsed and taken out according to the given data type by the programmer .

C The nature of data types in languages , This determines how this number is stored in memory , That is, it determines how to convert this number into binary . Memory is just a warehouse , It's full of 1 and 0, No matter inside 0 and 1 What does it mean to combine .