An attempt to explain pointers

pointers.c

#include <stdio.h>

/* NOTE:
 
 arr = refers to the array as a whole and/or the pointer to the first element of the array
 *arr = first element of an array
 
 */

int main( int argc, char** argv ){
    
	int arr[] = { 1,7,5,6 };
    
	int* ptr = arr; /* pointer to the first element of arr*/
    
	do{ /* we iterate until ptr is the same as the pointer to the last element in the array*/
        
		printf( "%d\n", *ptr ); /* we print the value associated with the pointer */
        
	} while( ptr++ !=  arr+((sizeof(arr)/sizeof(*arr))-1) );
    
    
    	/* 
        	This for loop does the same thing the do{...} while did
     	*/
    	for ( int* iter = arr; iter != arr+( sizeof(arr)/sizeof(*arr) ); iter++ ){
        
		printf( "for: %d\n", *iter );
	}
    
	return 0;
}