study of pointer to a pointer.

#include <stdio.h>

int main(void)
{
int num, *p, **p2p;

num = 2;

p = &num;

printf("\nnum = %d\t*p = %d", num, *p);

p2p = &p;

printf("\nnum = %d\t*p = %d\t**p2p = %d", num, *p, **p2p);

**p2p = 7;

printf("\nnum = %d\t*p = %d\t**p2p = %d", num, *p, **p2p);

return 0;
}