【C语言提高28】多级指针

#include<stdlib.h>
#include<stdio.h>
#include<string.h>
#include<ctype.h>


//产生molloc内存
char**getMem61(int num)
{

	int i = 0, j = 0;
	char** p2 = NULL;
	if (p2 == NULL)
	{
		return NULL;
	}
	p2 = (char**)malloc(sizeof(char*)*num);
	for (i = 0; i < num; i++)
	{
		p2[i] = (char*)malloc(sizeof(char) * 100);//相当于 char  buf[100];
		sprintf(p2[i], "%d%d%d", i + 1, i + 1, i + 1);//向内存空间中打印数据
	}

	return p2;
}

//利用三级指针返回二级指针
int getMem62(char***p2,int num)
{
	int i = 0;
	char**tmp = NULL;
	if (p2 == NULL)
	{
		return -1;
	}
	tmp = (char**)malloc(sizeof(char*)*num);

	*p2 = tmp;
	if (p2 == NULL)
	{
		return NULL;
	}
     
	for (i = 0; i < num; i++)
	{
		*p2[i] = (char*)malloc(sizeof(char) * 100);//相当于 char  buf[100];
		sprintf(*p2[i], "%d%d%d", i + 1, i + 1, i + 1);//向内存空间中打印数据
	}

	return 0;
}

//利用三级指针释放二级指针
void getMemFree62(char***p2, int num)
{
	int i = 0;
	char**tmp = NULL;
	if (p2 == NULL)
	{
		return;
	}

	tmp = *p2; 
	//释放所指向的内存空间
	for (i = 0; i < num; i++)
	{
		free(tmp[i]);
	}
	free(tmp);
	*p2 = NULL;//把实参置为NULL
}

void main()
{
	int i = 0, j = 0;
	char** p2 = NULL;
	char*tmp;
	char tmpbuf[100];
	int num = 5;
        getMem62(&p2,num);
	for (i = 0; i < num; i++)
	{
		printf("p2:%s",p2[i]);
	}

	printf("\nhehhe");
	system("pause");
	return;
}