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C二維數組用指針地址遍歷

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#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("********************行指針遍歷二維數組*************************\n");

	//二維數組的指針地址
	int fa[3][4] = {{1,2,3,4},{5,6,7,8},{9,10,11,12}};
	//行指針指針遍歷輸出二維數組
	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("******************用數組名 列指針遍歷二維數組***************************\n");
	//定義指針
	int *col = fa[0];//col是某行某列的指針 把第一行地址賦值給指針col
	for(;col<fa[0]+12; col++){
		//地址每次循環+1指向下一行一列
		if( (col-fa[0])%4==0 ){
			printf("\n");	
		}	
		printf("%d ", *col);
	}
	printf("******************用指針 列指針遍歷二維數組***************************\n");
	int *pp = *fa;
	int *arr = *fa;//二維數組首地址等同於 int *arr = fa[0]
	for(;arr<pp+12; arr++){
		//地址每次循環+1指向下一行一列
		if( (arr-pp)%4 == 0 ){
			printf("\n");	
		}	
		printf("%d ", *arr);
	}

	
	return 0;
	
}

  

C二維數組用指針地址遍歷