C and the pointer "I"

1. notes:

(1)/** * * * * * cannot be nested, and sometimes in a program there are comments, compilation will be problematic.

(2)#if 0 Statements #endif can compensate for the insufficiency of the first annotation.

2. The role of the statement: it is only required to be written once, easy to maintain and modify, eliminating the chance of inconsistent wording in multiple copies.

3.benefits of naming literal constants #define directives: increased code readability and ease of code modification

4.(pointer) dual indirect access: For example: **p

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The P pointer points to the Q address, i.e. p=&q;q points to a address, which is q=&a;*q=a=11;

*p=q=&a; **p=*q=a=11;

5. about * (p+1)

meaning: The essential meaning is to move the address in P to the next address, and then take the value  

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6. A segment error occurred: the memory accessed exceeds the memory space given to the program by the system.

7. Exchange values: Using pointers, the method of invocation:

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8. Memory Distribution

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9. The array name represents the first address of the array

such as:#include <stdio.h>

{

int a[5]={1,2,32,56,45};

int *pa=a;

printf ("%d\n", * (p+1));

}

The pointer variable is always expected to hold an address.

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C and the pointer "I"