指针赋值的区别，请指教

//有一个问题
#include <iostream.h>


struct Person
{
  char name[20];
  unsigned long id;
  float salary;


};
Person num[6]={{"jone",12345,339},
{"david",1382,449.0},{"marit",27614,311},{"jasen",4235,623},{"peter",23876,400},{"yoke",12335,511}};

void main()
{
    Person *p1[6]={&num[0],&num[1],&num[2],&num[3],&num[4],&num[5],};
    //Person *p1=num;替换上一句为什么不行？？？？？？？？？？
    Person *temp;
    for(int k=0;k<6;k++)
   {
      cout<<p1[k]->name<<endl;
  
   }
  /*
  最简单的一种方式
    Person temp;
    for(int i=1;i<6;i++)
        for(int j=0;j<6-i;j++)
        {
          if(p1[j]->salary>p1[j+1]->salary)
          {
            temp=p1[j];
            p1[j]=p1[j+1];
            p1[j+1]=temp;
         
         
          }
        
        
        }
  
  
  
  */


}