// *****************************************************************
// Author:	Zhixiang Chen
// Class:	CSCI/CMPE 2380, Spring 2009
// Lab 1:	Pointers, pointer arithmetic, pointers vs. arrays, 
//			pointer parameters
// Date:	January 13, 2009
// Comment: The code here is meant to be revised.
//
//-----------------------------------------------------------------
//
// This lab exercise is to practice pointers, pointer arithmetic, 
// pointers vs. arrays, and pointer parameters
// 
//
// Compile and run your program. When everything is fine,
// print your .h and .cpp files and turn them to me or the TA.
// *****************************************************************

#include < iostream >
#include <fstream >
#include < string >
#include < cstring >
#include < cmath> 
#include <cstdlib>
#include <iomanip>
#include <vector>					//include vector class template

//define a const array size
const int SIZE = 35;				//class size				
const int COLUMN = 11;				//column size

#include "lab2380_1_head.h" 

using namespace std; 


int main( )
{
	
	/************************************************************************
	 Part A: pointer declarations, operators:
			 * : dereference operator
			 & : address operator
			 . : member selection operator
			 ->: dereference member selection operator 
	 ************************************************************************/
	//simple pointers
	int cat, dog;						//two int vars
	int *intPtr;						//an int pointer
	cat = 10; 
	dog = 20; 
	intPtr = &cat;						//intPtr points to cat, i.e., intPtr has the address of cat
	cout << "cat is	   " <<cat <<",  "
		 << "dog is    " <<dog <<",  "
		 << "intPtr is " <<intPtr<<",  "
		 <<"*intPtr is " <<*intPtr<<endl; 
	
	dog = *intPtr;						//get what is pointed by intPtr to dog
	*intPtr = 55;						//change what is pointed by intPtr to 55

	intPtr = &cat;						//intPtr points to cat, i.e., intPtr has the address of cat
	cout << "cat is	   " <<cat <<",  "
		 << "dog is    " <<dog <<",  "
		 << "intPtr is " <<intPtr<<",  "
		 <<"*intPtr is " <<*intPtr<<endl; 

	//structure/class pointers
	studentType jane, joe;				//two students
	studentType *ptr;					//student pointer

	//using member selection operator . to access members of a structure/class
	jane.firstName="Alice";				//initilization
	jane.lastName="Smith";
	jane.grade='A'; 

	//using member selection operator . to access members of a structure/class
	joe.firstName="Alex";				//initilization
	joe.lastName="Black";
	joe.grade='B'; 

	ptr = &jane;						//ptr points to jane
	
	//use dereference member selection operator . to access members of a structure/class
	cout << ptr->firstName <<"  " 
		 << ptr->lastName  <<" got "
		 << ptr->grade << endl; 

	ptr = &joe;							//ptr points to joe

	//use dereference operator *, member selection operator ., and dereference member selection operator 
	//to access members of a structure/class
	cout << (*ptr).firstName <<"  " 
		 << (*ptr).lastName  <<" got "
		 << ptr->grade << endl; 
	

	/************************************************************************
	 Part B: Pointer arithemtic, arrays vs. pointers
	 ************************************************************************/
	//var declaration
	int a[5]={10, 20, 30, 40, 50};	//an int array of size 5
	studentType fun[3];					//a studentType array of size 3
	int *myPtr;							//an int pointer
	studentType *yourPtr;				//a studentType point
	int i;								//loop var

	//array name is a pointer pointing to the first element of the array
	//use array name pointer to access array elements
	cout<<"use array name ............ "<<endl; 
	for (i=0; i<5; i++)
	{
		cout<< *(a+i) <<" ";				//a+i is &a[i], *(a+i) is a[i]
	}
	cout<<endl; 

	myPtr = a; 
	cout<<"*myPtr = *a = a[0] = " << *myPtr<<endl; 
	myPtr = &a[1]; 
	cout<<"*myPtr = *(a+1) = a[1] = " << *myPtr<<endl;
	cout<<"What is *&a[2]? "         <<*&a[2]<<endl; 

	yourPtr = fun;						//youPtr points to the first element of fun array
	for (i=0; i<3; i++)
	{
		cout<<"Enter a first name => "; 
		cin>> (yourPtr+i)->firstName;  
		cout<<"Enter a first name => "; 
		cin>> (*(yourPtr+i)).lastName; 
		cout<<"Enter a grade => "; 
		cin>> yourPtr[i].grade;
	}
	//cout students
	yourPtr = fun; 
	for (i=0; i<3; i++)
	{
		cout << (yourPtr+i)->firstName <<"  "
			 << (*(yourPtr+i)).lastName <<" got " 
			 <<  yourPtr[i].grade <<endl; 					
	}

	/************************************************************************
	 Part C: Pointer parameter vs reference parameters vs value parameter
	 ************************************************************************/
	// var declaration
	int x =10, y=20; 
	int u=30, v=40; 
	int w=50, z=60; 
	//call swapOne with pointer type paramters
	cout<<"before calling swapOne(...), x is " << x << " and y is " <<y <<endl; 
	swapOne(&x, &y);					//watch, we pass &x and &y to this function!!!!!! 
	cout<<"after calling swapOne(...), x is " << x << " and y is " <<y <<endl; 

	//call swapTwo with reference type paramters
	cout<<"before calling swapTwo(...), u is " << u << " and v is " <<v <<endl; 
	swapTwo(u, v);					//watch, we pass u and v to this function!!!!!! 
	cout<<"after calling swapTwo(...), u is " << u << " and v is " <<v <<endl; 

	//call swapThree with value type paramters
	cout<<"before calling swapThree(...), w is " << w << " and z is " <<z <<endl; 
	swapThree(w, z);					
	cout<<"after calling swapThree(...), w is " << w << " and z is " <<z <<endl; 


	/*******************************************************************************
	 Part D: This part is for you to complete.
	         a. Define a new struct type 
				bookType with members of title, author, isbn, and price.
				
				You shall add the definition of the bookType into the header fil 
				lab2380_1_head.h.

			 b. Repeat Part A with variables of double type and bookTypes. 
			 b. Repeat Part B with char type arrays and variables
			 c. Repeat Part C with variables of bookType
	 *******************************************************************************/
	//Your code  is here

	//well done and exit
	return 0; 
}