CS256 - Principles of Structured Design Fall 2021

Displaying ./code/cs256su21code/jun29/pointers.c

/*

This just demonstrates accessing values through pointers

Note: When declaring pointers: you should initialize your pointer variables to NULL 
      if you don't have a variable to assign it to.

      Ex: int *ptr = NULL;

*/

#include <stdio.h>

int main(){


	int x = 5; //declaring an integer x, setting it equal to 5
	int *p = &x; //declaring a pointer, pointing it to the variable x using the assignment operator
	
	//should print 5 both times
	printf("Variable: %d\n", x);
	printf("Through pointer: %d\n", *p);

	//printf("Address stored in variable: %x\n", &p); //this prints the address

	x = 6; //change variable x to 6

	//both should print 6
	printf("Variable: %d\n", x);
	printf("Through pointer: %d\n", *p);	

	x++;//increment x

	//both should print 7
	printf("Variable: %d\n", x);
	printf("Through pointer: %d\n", *p);

	(*p)++; //increment x through the pointer
			//due to rules regarding operator precidence, we have
			//to have parentheses around the *p in order to increment a
			//number through the pointer

	//both should print 8
	printf("Variable: %d\n", x);
	printf("Through pointer: %d\n", *p);


	return 0;
}