In computer science, a pointer is a programming language object, whose value refers to (or "points to") another value stored elsewhere in the computer memory using its memory address. A pointer references a location in memory, and obtaining the value stored at that location is known as dereferencing the pointer. As an analogy, a page number in a book's index could be considered a pointer to the corresponding page; dereferencing such a pointer would be done by flipping to the page with the given page number.

1. Pointer Example

2. 1. What will be the output of the following code?
#include<stdio.h>
int func(int *p, int q)
{
*p =(*p)*q;
q =q*q;
return q;
}
int main(){
int m=5, n=6, o=2;
o=func(&m, n);
printf("M=%d N=%d O=%d",m,n,o);
return 0;
}
M=30 N=6 O=36

3. 2. What will be the output of the following code?
#include<stdio.h>
int* func(int *p, int *q)
{
*p =(*p)*(*q);
*q =(*q)*(*q);
return q;
}
int main(){
int m=5, n=6;
int *o=NULL;
o=func(&m, &n);
printf("M=%d N=%d O=%d",m,n,*o);
return 0;
}
M=30 N=36 O=36

4. 3. What will be the output of the following code?
#include<stdio.h>
int fun(int *m,int n);
int main()
{
int p=4,q=2,r=0;
r=fun(&p,q);
printf("P=%d Q=%d R=%d",p,q,r);
return 0;
}
int fun(int *m,int n)
{
(*m)++;
n++;
return *m+n;
}
P=5 Q=2 R=8

5. 4. What will be the output of the following code?
#include<stdio.h>
int fun(int m,int *n);
int main()
{
int p=5,q=3,r=1;
r=fun(p,&q);
printf("P=%d Q=%d R=%d",p,q,r);
return 0;
}
int fun(int m,int *n)
{
m++;
++(*n);
return m+*n;
}
P=5 Q=4 R=10

6. 5. What will be the output of the following code?
#include<stdio.h>
int main()
{
char Str[]= "Best of Luck";
char *ptr;
ptr = Str;
printf("n1. %s", ptr);
printf("n 2.%s", ++ptr);
Str[8] = '0';
printf("n 3.%s", Str);
printf("n 4.%s", ++ptr);
return 0;
}
1. Best of Luck
2. est of Luck
3. best of
4. st of