int main()
{int i=5;           //假设  &i =0x100int *p=&i;         //假设  &p =0x500int **pp=&p;       //假设  &pp=0x1000/*所以 &i=0x100,i=5&p=0x500   p =0x100  *p=5&pp=0x1000   pp=0x500  *pp=0x100   **pp=5
        */
}

#include <stdio.h>void func(int arrs[][2])
{arrs[0][2]=100;
}int main()
{int arrs[8][2];func(arrs);printf("arrs[0][2]=%d\n",arrs[0][2]);return 0;
}

void *malloc(int size);

void free(void *ptr);

char *p;char str[]="ABCD";      p= (char *)malloc(strlen(str));     //必须使用指针获取,并强制转换

strcpy(p,str);... ...free(p);

#include "stdio.h"
#include <stdlib.h>
#include  "string.h"typedef struct NAME{     char   *name;struct NAME *preced;   //上个name链表成员struct NAME *next;     //下个name链表成员
}T_NAME, *PT_NAME;PT_NAME  g_ptNameListHead=NULL;                     //链表头void add_LinkList(PT_NAME nameNew)
{PT_NAME ptTamp;int i=0;if(g_ptNameListHead==NULL)     //第一次添加链表{g_ptNameListHead= nameNew;return ;}else{ptTamp=g_ptNameListHead;while(ptTamp->next)          //下个链表成员是否为空{ptTamp=ptTamp->next;}ptTamp->next=nameNew;         //添加下个链表成员
nameNew-> preced= ptTamp;   //在下个链表成员里添加上个链表   return ; }
}void add_name(char str[])
{PT_NAME   ptTamp;char *p; p=(char *)malloc(strlen(str));strcpy(p,str);ptTamp=(PT_NAME)malloc(sizeof(T_NAME));ptTamp->name=p;ptTamp-> preced=NULL;ptTamp-> next= NULL;add_LinkList(ptTamp);   //添加链表
}/*从链表里找到name位置*/
PT_NAME find_name(char str[])
{PT_NAME ptTamp;if(g_ptNameListHead==NULL)return NULL;ptTamp=g_ptNameListHead;while(ptTamp){if(strcmp(ptTamp->name,str)==0)             //find{return  ptTamp;}elseptTamp=ptTamp->next;}return NULL;}int del_name(char str[])
{PT_NAME ptTamp;PT_NAME ptLast;PT_NAME ptNext;ptTamp=find_name(str);if(!ptTamp)return -1;if(ptTamp==g_ptNameListHead)    //若去掉的是链表头{g_ptNameListHead=ptTamp->next;    //指向下个链表成员}else{/*获取上个链表成员和下个链表成员*/ptLast=ptTamp->preced;      ptNext=ptTamp->next ;/*去掉当前链表成员*/ptLast->next= ptNext;ptNext->preced=ptLast;}free(ptTamp->name);free(ptTamp);return 0;
}void List_name(void)
{int i=0;PT_NAME ptTamp=g_ptNameListHead;while(ptTamp){printf("<%d> %s\n",i,ptTamp->name);        ptTamp=ptTamp->next;}
}void  scanf_name(char cmd)
{char name[128];switch(cmd){case 'a':               //add{printf("please enter name:\n");scanf("%s",name);add_name(name);printf("add %s OK\n",name);break;}case  'd':                    //del{printf("please enter name:\n");scanf("%s",name);if(del_name(name)<0){printf("del %s error\n",name);}elseprintf("del %s OK\n",name);     break;}case 'l':                //listList_name(); break;}
}int main(int argc, char **argv)
{char c;while(1){printf("**********************\n");printf("<l> List all the names\n");printf("<a> add one name\n");printf("<d> del one name\n");printf("<q> quit\n");printf("**********************\n");do{scanf("%c",&c);}while(c!='a'&&c!='d'&&c!='q'&&c!='l');   switch(c){case 'a':case 'l':case 'd':scanf_name(c);  break;case 'q':return 0;default : break;}}
}