C Programming

CLASS EXERCISE C23
Determine the output of the pointer programs P1, P2, and P3.

	/* P1.C  illustrating pointers */
	#include <stdio.h>

	main()
	{
		int count  = 10, x, *int_pointer;

		/* this assigns the memory address of count to int_pointer  */
		int_pointer = &count;

		/* assigns the value stored at the address specified by int_pointer to x */
		x = *int_pointer;

		printf("count = %d, x = %d\n", count, x);
	}


	count = 10, x = 10;

/* P2.C  Further examples of pointers */
	#include <stdio.h>

	main()
	{
		char c = 'Q';
		char *char_pointer = &c;

		printf("%c %c\n", c, *char_pointer);

		c = '/';
		printf("%c %c\n", c, *char_pointer);
		*char_pointer = '(';
	/* assigns ( as the contents of the memory address specified by char_pointer  */

		printf("%c %c\n", c, *char_pointer);
	}


	Q Q
	/ /
	( (

/* P3.C  Another program with pointers */
	#include <stdio.h>

	main()
	{
		int i1, i2, *p1, *p2;

		i1 = 5;
		p1 = &i1;
		i2 = *p1 / 2 + 10;
		p2 = p1;

		printf("i1 = %d, i2 = %d, *p1 = %d, *p2 = %d\n", i1, i2, *p1, *p2);
	}


	i1 = 5, i2 = 12, *p1 = 5, *p2 = 5

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