C二维数组用指针地址遍历

时间:2023-03-10 03:39:06
C二维数组用指针地址遍历
#include <stdio.h>
#include <stdlib.h>
int main(){
int a = 100;
void *p = &a;
printf("a:%d address:%p\n",*(int*)p, &a);
//unsigned int *pt = (unsigned int*)0xbfa70ee8;
int *pt = (int*)malloc(sizeof(int));
*pt = 200;
printf("ptv:%p v:%d\n",pt,*pt); printf("********************行指针遍历二维数组*************************\n"); //二维数组的指针地址
int fa[3][4] = {{1,2,3,4},{5,6,7,8},{9,10,11,12}};
//行指针指针遍历输出二维数组
int i,j;
for(i=0;i<3;i++)
{
for(j=0;j<4;j++){
printf("fa[%d][%d]=%d %p\n",i,j, *(*(fa+i)+j),*(fa+i)+j);
}
}
printf("******************用数组名 列指针遍历二维数组***************************\n");
//定义指针
int *col = fa[0];//col是某行某列的指针 把第一行地址赋值给指针col
for(;col<fa[0]+12; col++){
//地址每次循环+1指向下一行一列
if( (col-fa[0])%4==0 ){
printf("\n");
}
printf("%d ", *col);
}
printf("******************用指针 列指针遍历二维数组***************************\n");
int *pp = *fa;
int *arr = *fa;//二维数组首地址等同于 int *arr = fa[0]
for(;arr<pp+12; arr++){
//地址每次循环+1指向下一行一列
if( (arr-pp)%4 == 0 ){
printf("\n");
}
printf("%d ", *arr);
} return 0; }