/*
 * w1_c2_lecture.cpp
 *
 *  Created on: Mar 4, 2019
 *      Author: johnsontimoj
 */
///////////////////////////////////
//
// Week1 - Class2 Lecture examples
//
/////////////////////////////////////
#include <iostream>
using namespace std;

#include "w1_c2_lecture.h"

int main(void){

	///////////////
	// Simple IO
	//////////////
	// simple output
	cout << "Hello World\n";

	/////////////////////////////////
	// simple input
	int val;
	cout << "Please enter a value: ";
	cin >> val;
	cout << "You entered the value: " << val << endl;

	/////////////////////////////////
	// gated input
	val = 0;
	cout << "Please enter the value -1" << endl;
	while(val != -1){
		cin >> val;
	} // end while
	cout << "Finally !\n";

	//////////////////////////////////
	// multiple input
	int val1;
	int val2;
	int val3;
	cout << "please enter 3 values: ";
	cin >> val1 >> val2 >> val3;
	cout <<"You entered: " << val1 << val2 << val3 << "\n";

	//////////////
	// pointer review
	//////////////
	// basic pointer use
	int val4;
	read_val(&val4);
	print_val(val4);

	/////////////////////////////////////
	// alternate pointer use
	int val5;
	int * val5_ptr;
	val5_ptr = &val5;
	read_val(val5_ptr);
	print_val(val5);

	////////////////
	// Dynamic memory
	///////////////
	// Show the difference in memory locations
	int val6;
	int val7;
	int * val8_ptr = new int;
	int * val9_ptr = new int;
	read_val(&val6);
	read_val(&val7);
	read_val(val8_ptr);
	read_val(val9_ptr);
	print_val(val6);
	print_val(val7);
	print_val(*val8_ptr);
	print_val(*val9_ptr);
	delete val8_ptr;
	delete val9_ptr;

	//////////////////////////////////

	// Show the use of new with multiple number of elements
	int * valA_ptr = new int[4];
	read_val(valA_ptr);
	read_val(valA_ptr + 1);
	read_val(&valA_ptr[2]);
	read_val(valA_ptr + 3);
	print_val(*valA_ptr);
	print_val(valA_ptr[1]);
	print_val(*(valA_ptr + 2));
	print_val(valA_ptr[3]);
	delete[] valA_ptr;

	//////////////////////////////////

	// Show the use of new with intermediate delete
	int * valB = new int;
	read_val(valB);
	delete valB;
	int * valC = new int;
	read_val(valC);
	delete valC;

	//////////////////////////////////

	//
	// Plus File stream example from notes
	//

	return 0;
} // end main

//
// Function passing back the value read "by pointer"
//
void read_val(int * value){
	cout << "Please enter a value: ";
	cin >> *value;
	// print out the actual value passed to the function
	// since a pointer is passed - this will be the address
	// of the variable referenced by the pointer
	cout << "The value passed to the read_val function was: " << value << endl;
	return;
} // end read_val

//
// Function printing a value "passed by value"
//
void print_val(int value){
	cout << "You entered: " << value << endl;
	return;
} // end print_val