C Language Arrays Iterating through an array using pointers


Example

#include <stdio.h>
#define SIZE (10)
int main()
{
    size_t i = 0;
    int *p = NULL;
    int a[SIZE];
    
    /* Setting up the values to be i*i */
    for(i = 0; i < SIZE; ++i) 
    {
        a[i] = i * i;
    }
    
    /* Reading the values using pointers */
    for(p = a; p < a + SIZE; ++p) 
    {
        printf("%d\n", *p);
    }

    return 0;
}

Here, in the initialization of p in the first for loop condition, the array a decays to a pointer to its first element, as it would in almost all places where such an array variable is used.

Then, the ++p performs pointer arithmetic on the pointer p and walks one by one through the elements of the array, and refers to them by dereferencing them with *p.