Here, we will demonstrate pointer operations in C programming.

#include
#include
void main(){

    int arr[5]={12,13,14,15,16};
    int *ptrArr, *ptrArr1,i;
    clrscr();
    
    ptrArr = arr;
    printf("\nPrinting the first element of array: %d\n\n",*ptrArr);
    
    /*Pointer variable can be increased. If added 1 to it, it will point to the
    next element of the same array*/

    for(i=0;i<5;i++){
        printf("%d\t", *ptrArr);
        ptrArr++;
    }
    printf("\n\n");


    /*Now the Pointer is pointing to a memory location that is not reserved
    so if you will print the value at pointer location it will print garbage
    and some times it show any RUN TIME error because C compiler will not
    check array boundaries*/

    printf("Printing value at pointer location that is not reserved by the program\n");
    printf("%d This is garbage\n\n",*ptrArr);
  
    /*Pointer varible can be decreased and if we are decreasing 1 to it,
    it will start pointing to the previous element in the same array*/

    for(i=0;i<5;i++){
        ptrArr--;
        printf("%d\t", *ptrArr);
    }
    printf("\n\n");

	/*Now, ptrArr will point to 3rd element of array*/

	ptrArr = &arr[2];

	printf("\nThird element of an array : %d",*ptrArr);

	/*One pointer can be subtracted from another if they are poining to
    elements of same array and the operation will return no of elements
    in between these two pointer locations*/

	ptrArr1 = &arr[5];

	printf("\n\nSubtraction of two pointers ptrArr1 - ptrArr : %d\n",ptrArr1 - ptrArr);

    getch();
    }

Note:
Two Pointers cannot be added
A pointer cannot be multipled with a number
A pointer cannot be divided by a number

Output:

Printing the first element of array: 12

12 13 14 15 16

Printing value at pointer location that is not reserved by the program
0 This is garbage

16 15 14 13 12

Third element of an array : 14

Subtraction of two pointers ptrArr1 - ptrArr : 2

Article on Pointers in C Programming Language