An austere program using C pointers

 C Cheat Sheet for introduction to Pointers 101:

	// Program x.y An austere program using C pointers.
	/*
	1. num's address: 0x7ffe83ecb46c
	2. num's value: 13
	3. pt's address: 0x7ffe83ecb470
	4. pt' size: 8 bytes
	5. pt's value: 0x7ffe83ecb46c
	6. value pointed to: 13
	7. new num value to: 18
	pp = 0x7ffd4799a3b0, ptr = 0x7ffd4799a3b0
	*pp = 3, *ptr = 0x7ffd4799a3b0
	*/
	#include <stdio.h>
	int main(void)
	{
	int num = 0; // A variable of type int initialized to 0
	int *pt = NULL; // A pointer that can point to type int
	num = 13;
	printf("1. num's address: %p\n", &num); // Output the address
	printf("2. num's value: %d\n", num); // Output the value
	pt = &num; // Store the address of num in pt
	printf("3. pt's address: %p\n", (void*)&pt); // Output the address (void pointer = handles any data type)
	printf("4. pt' size: %zd bytes\n", sizeof(pt)); // Output the size
	printf("5. pt's value: %p\n", pt); // Output the value (an address)
	printf("6. value pointed to: %d\n", *pt); // Value at the address (* dereference operator, deferring the pointer)
	*pt = *pt + 5;
	printf("7. new num value to: %d\n", num); // Value at the address (* dereference operator, deferring the pointer)
	int arr[] = { 3, 5, 6, 7, 9 };
	int *pp = arr;
	int (*ptr)[5] = &arr;
	printf("pp = %p, ptr = %p\n", pp, ptr);
	printf("*pp = %d, *ptr = %p\n", *pp, *ptr);
	return 0;
	}

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