#include<stdio.h>

 void main(){

  int A = 10;

  printf("Value of A is %d\n",A);

  printf("Address of A is %d\n",&A);

  int *P

  P = &A;

  printf("Value of P is %d\n",P);

  printf("Address of P is %d\n",&P);

  printf("Value at the address in P is %d\n",*P);

  *P = 20;

  printf("New Value of A is %d\n",A);

 }