# Difference between ++*p, *p++ and *++p in C

## Pointer Airthmetics

In C programming language, *p represents the value stored in a pointer. ++ is increment operator used in prefix and postfix expressions. * is dereference operator. Precedence of prefix ++ and * is same and both are right to left associative. Precedence of postfix ++ is higher than both prefix ++ and * and is left to right associative. See the below example to understand the difference between ++*p, *p++ and *++p.

### Example (C)

Live Demo

#include <stdio.h>
int main() {
int arr[] = {20, 30, 40};
int *p = arr;
int q;
//value of p (20) incremented by 1
//and returned
q = ++*p;
printf("arr[0] = %d, arr[1] = %d, *p = %d, q = %d ",
arr[0], arr[1], *p, q);
//value of p (20) is returned
//pointer incremented by 1
q = *p++;
printf("arr[0] = %d, arr[1] = %d, *p = %d, q = %d ",
arr[0], arr[1], *p, q);
//pointer incremented by 1
//value returned
q = *++p;
printf("arr[0] = %d, arr[1] = %d, *p = %d, q = %d ",
arr[0], arr[1], *p, q);
return 0;
}

## Output

arr[0] = 21, arr[1] = 30, *p = 21, q = 21
arr[0] = 21, arr[1] = 30, *p = 30, q = 21
arr[0] = 21, arr[1] = 30, *p = 40, q = 40