基本介绍
1.指针数组:由n个指向整型元素的指针而组成,里面存放指针
Int *ptr[3];
2.地址:
ptr[i]:元素地址
&ptr[i]:指针地址
图示
代码:
内存布局:
代码
#include<stdio.h>
#include<string.h>
//指针数组--int
void pointer(int *arr,int len)
{int i, *ptr[10];for(i=0;i<len;i++){ptr[i]=&arr[i];printf("arr[%d]=%d address=%p\n",i,arr[i],&arr[i]);printf("ptr[%d]=%d address=%p self-address=%p\n",i,*ptr[i],ptr[i],&ptr[i]);}
}//指针数组--char
void cpointer(char* s,int len)
{char *c[4];int i=0;printf("s=%s address=%p self-address=%p\n",s,s,&s);while(i<len){c[i]=&s[i];printf("c[%d]=%c address=%p self-address=%p\n",i,*c[i],c[i],&c[i]);i++;}
}void cpointer2(char *s,int len)
{char *c[4];int i;printf("s=%s address=%p self-address=%p\n",s,s,&s);for(i=0;i<len;i++){c[i]=&s[i];}char *p=c[0];for(i=0;i<len;i++){printf("c[%d]=%c address=%p self-address=%p\n",i,*p,p,&p);p++;}
}
int main()
{int i,arr[10];int len=sizeof(arr)/sizeof(int);char *s="uiop";for(i=0;i<len;i++){arr[i]=99;}printf("int_pointer:\n");pointer(arr,len);printf("char_pointer:\n");cpointer(s,strlen(s));printf("char_pointer2:\n");cpointer2(s,strlen(s));getchar();return 0;
}
输出:
int_pointer:
arr[0]=99 address=010FF984
ptr[0]=99 address=010FF984 self-address=010FF854
arr[1]=99 address=010FF988
ptr[1]=99 address=010FF988 self-address=010FF858
arr[2]=99 address=010FF98C
ptr[2]=99 address=010FF98C self-address=010FF85C
arr[3]=99 address=010FF990
ptr[3]=99 address=010FF990 self-address=010FF860
arr[4]=99 address=010FF994
ptr[4]=99 address=010FF994 self-address=010FF864
arr[5]=99 address=010FF998
ptr[5]=99 address=010FF998 self-address=010FF868
arr[6]=99 address=010FF99C
ptr[6]=99 address=010FF99C self-address=010FF86C
arr[7]=99 address=010FF9A0
ptr[7]=99 address=010FF9A0 self-address=010FF870
arr[8]=99 address=010FF9A4
ptr[8]=99 address=010FF9A4 self-address=010FF874
arr[9]=99 address=010FF9A8
ptr[9]=99 address=010FF9A8 self-address=010FF878
char_pointer:
s=uiop address=006B5814 self-address=010FF894
c[0]=u address=006B5814 self-address=010FF878
c[1]=i address=006B5815 self-address=010FF87C
c[2]=o address=006B5816 self-address=010FF880
c[3]=p address=006B5817 self-address=010FF884
char_pointer2:
s=uiop address=006B5814 self-address=010FF894
c[0]=u address=006B5814 self-address=010FF860
c[1]=i address=006B5815 self-address=010FF860
c[2]=o address=006B5816 self-address=010FF860
c[3]=p address=006B5817 self-address=010FF860字符数组指针
具体分析
#include<stdio.h>
#include<string.h>
int main()
{char *p[]={"水浒传","三国演义","西游记","红楼梦"};int i=0;printf("方法1:\n");for(i=0;i<4;i++){/*字符指针char *pstr="good dog ww";printf("字符指针指向的字符串内容:%s\n",pstr);所以这里的%s-->p[i]数组:地址传递(指针)%c *pstr是取出一个字符这里不能*p[i],p[i]本身就是一个字符数组指针,无法单独取出一个字符*/
//p[0]="水浒传" %s p[0]就直接是取出字符串printf("p[%d]=%s address=%p self-address=%p\n",i,p[i],p[i],&p[i]);}printf("方法2:\n");char *ptr=p[0];i=0;while(i<=3){printf("p=%s address=%p self-address=%p\n",ptr,ptr,&ptr);i++;ptr=p[i];//每一个p[i]的字符内容不同,导致其间隔不同,所以不能使用ptr++}getchar();return 0;
}
整型数组指针
#include<stdio.h>
#include<string.h>
//整型指针
int main()
{int a=1,b=2,c=4,d=90;int*a1=&a,*a2=&b,*a3=&c,*a4=&d;int *arr[]={a1,a2,a3,a4};int i;printf("方法1:\n");for(i=0;i<4;i++){//arr[0]=a1=&a=1的地址--%d arr[i]只会取到地址//*arr[i]才能取到值printf("arr[%d]=%d address=%p self-address=%p\n",i,*arr[i],arr[i],&arr[i]);}printf("方法2:\n");i=0;int *p=arr[0];while(i<=3){printf("arr[%d]=%d address=%p self-address=%p\n",i,*p,p,&p);i++;p=arr[i];//p++不行 随机存储的,+1不是下一个元素的地址}getchar();return 0;
}
区分
指针数组:
由n个指向整型元素的指针而组成,里面存放指针
Int *ptr[3];
数组指针:
指向一个有n个元素的数组的指针,里面存放的是整型变量(int类型长度为n的数组的首地址),存的是一个数组地址,而不是单个元素
int(*p)[n]
代码详解
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
//指针使用 int(*p)[n]与int *p[n]的区别
int main()
{int i;// int(*p)[n]--指向一个有n个元素的数组的指针,里面存放的是整型变量(int类型长度为n的数组的首地址)//存的是一个数组地址,而不是单个元素int a[3]={1,2,3};int b[3][3]={{1,4,0},{2,5,6},{7,6,8}};int(*arr)[3]=b;printf("int(*arr)[n]:\n");for(i=0;i<3;i++){printf("arr[%d]=%d address=%p self-address=%p\n",i,*arr[i],arr[i],&arr[i]);}//int *p[n]--指针数组,由n个指向整型元素的指针而组成,里面存放指针int *p[3];for(i=0;i<3;i++){p[i]=&a[i];}printf("int*p[n]:\n");for(i=0;i<3;i++){//数组printf("arr[%d]=%d address=%p self-address=%p\n",i,*p[i],p[i],&p[i]);}getchar();return 0;
}
