#include <stdio.h>
main()
{
int i;
int *pi = &i; // pi pointing to address of i
scanf("%d", pi); /* means store the inputted value by scanf at location/address pointed by pi. i.e at variable int i. earlier int i was holding garbage value. now it will store input value given by you. let say you input the value of i=10; */
printf("%d\n", i+5); // add 5 in int i. i.e 10+5 =15
}
so final output will be 5 more than entered value by you.