array and pointer

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1: 

const char **  and char **


const char ** ==> const char * 

char ** ==> char *



2: 

array

int a[10]


a as a right value

b = a == > char ((char *)a) length = 1

b = &a ==>  length = sizeof(int) * 10

b = &a[0] ==> int a[0]


xxtype a[10];


a ==> address value ==> (typeof  a[0])* a[0] 


int a[10];


a is an address value, not an int value;

a is only  a right value, not a left value ,  pointer  (which contains address value of a) doesn't exist. without memory space to contain the address of a.

type of a is a pointer which point to type of a[0]

length of a is  a[0] -- a[length] (NOTE: length is  0, 1, 2, .. length, NOT (length - 1), the total number elements  which can accessed by a is (length  + 1)), a[-1] , or a[length + 1] is illegal.


3: 

pointer and array

C Language type

type = first address + space length


4: 

array as pointer

a[10] 

p = a

p-- -- xx

p+1

p+2 

..

p+9 -- OK

p+10 -- OK

p+11 -- xx



5:

二维数组和二级指针是两码事。

无论多少维度的数组,都是一级指针,参数用fun(int *array)即可接收。

二级指针(指向指针的指针)是这样用的:

1
2
3
int  a[5][5];
void fun(int **array,int n);
fun(&a,n);//将指针的地址传送过去



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