求解！怎么改才能让num值为3

#include<stdio.h>
void Printf(char *arr[],int len);
int main(void)
{
char *parray[]={"how","are","you"};
int num=sizeof(parray)/sizeof(char);
printf("total string numbers=%d\n",num);
Printf(parray,num);
return 0;
}
void Printf(char *arr[],int len)
{
int i;
for(i=0;i<len;i++)
{
printf("%s",arr[i]);
}
printf("\n");
}

这么改：int num=sizeof(parray)/sizeof(*parray);