C Language > Pointers

C language arrays and pointers

Const

There are some rules to note about pointers and Const. First, it is legal to initialize the address of the const data or non-const data to a pointer to a const or to assign a value to it.

However, you can only assign addresses of non-const data to normal pointers. (That is, a const value cannot be assigned to a normal pointer);

Pointers and multidimensional arrays:

Zippo = &zippo[0];

zippo+2 = = &zippo[2];

* (zippo+2) = = &zippo[2][0];

* (zippo+2) + 1 = = &zippo[2][1];

* (* (zippo+2) + 1) = = Zippo[2][1];

Pointer to multidimensional array:

Int (* PZ) [2]; >> PZ points to an array containing two int types;

( such as: zippo[4][2];)

INT * Pax[2]; >> Pax is an array of two pointer elements, each of which points to an int pointer;

( just like the meaning of the array, it declares two pointers, one is pax[0] and the other is pax[1])

(such as pax [0] = Zippo; pax[1] = ZIPPP; >> *pax[0] = = *pax[1];)

An array variable is a const pointer, so it cannot be assigned a value:

int a[] <==> int * Const A = ....

The array variable itself expresses the address, so:

int a[10]; int * p = A; No need to take & address

But the cell expression of an array is a variable, it needs to use & address

A = = &a[0]

The [] operator can do the array, or it can do the pointer:

P[0] <==> a[0];

* the operator can do the pointer, or it can do the array:

*a = 25;

C Language > Pointers