Explain statement 2 and 3 in the given c++ code?

Question

#include <iostream.h>
#include<conio.h>
int main()
{
clrscr();
static int a[]={0,1,2,3.4};
int *p[]={a,a+1,a+3,a+4}; //statement 2
int **ptr=p; //statement 3
ptr++;
cout<<ptr-p<<*ptr-a<<**ptr<<endl;
*ptr++;
cout<<ptr-p<<*ptr-a<<**ptr<<endl;
++*ptr;
cout<<ptr-p<<*ptr-a<<**ptr<<endl;
getch();
}

Answer 1

statement 2 is array of pointer and statement 3 is chain of pointer (pointer to pointer).