// PointersAndStructures.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
struct student {
	int id;
	int grade;
	float gpa;
};

struct student s1, s2, s3, temp;

int _tmain(int argc, _TCHAR* argv[])
{
	s1.id = 25342;
	s1.grade = 9;
	s1.gpa = 3.655;
	s2.id = 27882;
	s2.grade = 12;
	s2.gpa = 3.220;
	s3.id = 12663;
	s3.grade = 11;
	s3.gpa = 2.709;

	printf("Student Id:    Grade Level:    GPA:\n\n");
	printf("s1: %8d          %4d           %5.3f\n", s1.id, s1.grade, s1.gpa);
	printf("s2: %8d          %4d           %5.3f\n", s2.id, s2.grade, s2.gpa);
	printf("s3: %8d          %4d           %5.3f\n", s3.id, s3.grade, s3.gpa);

    printf("\n\nNow, we swap students 1 and 2\n\n");

	temp.id = s1.id;
	temp.grade = s1.grade;
	temp.gpa = s1.gpa;

	s1.id = s2.id;
	s1.grade = s2.grade;
	s1.gpa = s2.gpa;

	s2.id = temp.id;
	s2.grade = temp.grade;
	s2.gpa = temp.gpa;

	printf("Student Id:    Grade Level:    GPA:\n\n");
	printf("s1: %8d          %4d           %5.3f\n", s1.id, s1.grade, s1.gpa);
	printf("s2: %8d          %4d           %5.3f\n", s2.id, s2.grade, s2.gpa);
	printf("s3: %8d          %4d           %5.3f\n", s3.id, s3.grade, s3.gpa);


	printf("Now, using pointers:\n\n");

    struct student *pointer1, *pointer2, *pointer3, *temp_ptr;

    pointer1 = &s1;
	pointer2 = &s2;
	pointer3 = &s3;

	printf("Student Id:    Grade Level:    GPA:\n\n");
	printf("s1: %8d          %4d           %5.3f\n", pointer1->id, pointer1->grade, pointer1->gpa);
	printf("s2: %8d          %4d           %5.3f\n", pointer2->id, pointer2->grade, pointer2->gpa);
	printf("s3: %8d          %4d           %5.3f\n", pointer3->id, pointer3->grade, pointer3->gpa);

    printf("\n\nNow, we swap students 2 and 3\n\n");

	temp_ptr = pointer2;
	pointer2 = pointer3;
	pointer3 = temp_ptr;

	printf("Student Id:    Grade Level:    GPA:\n\n");
	printf("s1: %8d          %4d           %5.3f\n", pointer1->id, pointer1->grade, pointer1->gpa);
	printf("s2: %8d          %4d           %5.3f\n", pointer2->id, pointer2->grade, pointer2->gpa);
	printf("s3: %8d          %4d           %5.3f\n", pointer3->id, pointer3->grade, pointer3->gpa);

	return 0;
}