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Through the previous article, we have a basic understanding of pointers , I see. It's just something with an address , But the use of relative pointers , I'll talk again about the basic uses of pointers ;
Pointer operation ：
The pointer can also be ++,-- perhaps +,- Operation of , But the budget of the pointer is limited to this ,++,+ Represents that the pointer moves forward ,--,-
Represents a backward movement of the pointer . It also refers to the forward or backward address it refers to ;
Like the next program ：
int a[10]; int *p; p = &a; //p point a array i = 0; for(i;i<10;i++) {
printf("%p",p);// Output now p Position indicated P ++; //p Add one to the indicated position }
This program outputs a Address of items in the array ;
When the address of an array is given to a pointer , When this pointer refers to
a【0】 Address of , That is, the address of the first number in the array , Because of the array arrangement , The given location space in memory is continuous , So when we add one to the value indicated by the pointer , That means pointing to the next address in the array ;
Relational operation of pointer ：
Relationship between two pointers , Size, etc , The comparison refers to the relationship between the addresses , And the size of the address , By ASC|| Code ; It's like ：
int a,*p,*d;
*p = &a;
When in this case
We say *p == *d; This would be a fake ;
*d = &a;
*p == *d;
under these circumstances , This will be true , Only when two pointers point to one address at the same time , Then the two pointers can be said to be equal .
Relationship between pointer and array ：
Next, let's focus on the relationship between pointers and arrays , How do they use each other ;
As we mentioned above , When the pointer points to a one-dimensional array , The address it refers to is the address of the first value of the array , When the pointer is performing an operation +, - Hour , Corresponding , The address it refers to will also change ;
When the pointer points to a multidimensional array , In fact, it is similar to pointing to a one-dimensional array , The changes were like this
a【2】【2】; In this array , We let *p=&a;
initial p Is pointing a【0】【0】;
When p++ Hour , Will point to a【0】【1】; Next is a【0】【2】;a【1】【0】;a【1】【1】; and so on ;
about int a【3】【4】,*p = a【0】;
Address description meaning the description meaning of array elements
a,*a,a【0】,&a【0】【0】,pa First address of **a,*p,*a【0】, a【0】【0】a【0】【0】 Value of
*a+1,a【0】+1,&a【0】【0】+1,p+1a【0】【1】 Address of *（*a+1）,*（p+1）, a【0】【1】,
*{a【0】+1）, *（&a【0】【0】+1a【0】【1】 Value of
a+1a【1】【0】 Address of
**(a+1),*a【1】,a【1】【0】
a【1】【0】 Value of
a+ia【i】【0】 Address of **（a+i）,*a【i】, a【i】【0】a【i】【0】 Value of
*a+ix4+j,p+ix4+j,a【0】+ix4+j,&a【0】【0】+ix4+j,&a【i】【j】a【i】【j】 Address of
*（*a+ix4+j）,*（p+ix4+j）, *（a【0】+ix4+j）, a【i】【j】,*（&a【0】【0】+ix4+j）
a【i】【j】 Value of
Through this table , We can basically have a more comprehensive understanding of the relationship between pointers and multidimensional arrays .
notes ： For clarity of Blog , I use 【】 instead of [] , Don't learn from me , Use English input method .
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