/*
   Computer Science & Programming 
   Jason M. Snouffer
   Wednesday, October 16, 2002

   Lab 7 Problem 2

	This program reads an integer from a file, and prints out a times table from 1 to 12 times that number.

   Test Suite:

	Input				Output


	1					1*1 = 1
						1*2 = 2
						1*3 = 3
						1*4 = 4
						1*5 = 5
						1*6 = 6
						1*7 = 7
						1*8 = 8
						1*9 = 9
						1*10 = 10
						1*11 = 11
						1*12 = 12


  	-5					-5*1 = -5
						-5*2 = -10
						-5*3 = -15
						-5*4 = -20
						-5*5 = -25
						-5*6 = -30
						-5*7 = -35
						-5*8 = -40
						-5*9 = -45
						-5*10 = -50
						-5*11 = -55
						-5*12 = -60


  	7					7*1 = 7
						7*2 = 14
						7*3 = 21
						7*4 = 28
						7*5 = 35
						7*6 = 42
						7*7 = 49
						7*8 = 56
						7*9 = 63
						7*10 = 70
						7*11 = 77
						7*12 = 84


  	30					1*1 = 30
						1*2 = 60
						1*3 = 90
						1*4 = 120
						1*5 = 150
						1*6 = 180
						1*7 = 210
						1*8 = 240
						1*9 = 270
						1*10 = 300
						1*11 = 330
						1*12 = 360

	All of the sample inputs within this test suite were tested and performed as expected.
*/

#include <fstream>
#include <iostream>
#include <cstdlib>

using namespace std;

/* This program is a simple demonstration of how to read and write
 * files in C++ using input and output streams.
 *
 * For now, don't worry about how this stuff works. All you need to
 * know, is that if you copy and paste everything except main in this
 * file, that you can write a main that uses these functions.
 *
 */


//----------------- open_output_file_stream ---------------------
/* 
 * This function returns an object of type ofstream that gives the
 * user a way to write to the file filename. If filename
 * is not a valid file, then this function halts the program using 
 * the exit command.
 * 
 * 
 * pre: filename should be the name of a file in the same 
 *      folder as the program itself.
 * 
 */

ofstream open_output_file_stream(char *filename);


//----------------- open_input_file_stream ---------------------
/* 
 * This function returns an object of type ifstream that gives the
 * user a way to read from the file filename. If filename
 * is not a valid file, then this function halts the program using 
 * the exit command.
 * 
 * 
 * pre: filename should be the name of a file in the same 
 *      folder as the program itself.
 * 
 */

ifstream open_input_file_stream(char *filename);


  


int main()
{
	// special cin and cout streams are instances of a special type
	// I used the variable names panda_bear and sea_lion just so you'd
	// know that they didn't have to be anything special. These
	// are BAD variable names It would be much better to call
	// panda_bear in_stream and sea_lion out_stream

	
	ifstream input_stream = open_input_file_stream ("../Lab 7/number_in.txt");
	
	int num;
	input_stream>>num;
	
	int i;
	
	for(i = 1; i <= 12; i++)
	{
		cout<<num<<'*'<<i<<" = "<<i * num<<endl;
	}
	
	input_stream.close();
	
	return (EXIT_SUCCESS);
	
}


//----------------- open_output_file_stream ---------------------
/* 
 * This function returns an object of type ofstream that gives the
 * user a way to write to the file filename. If filename
 * is not a valid file, then this function halts the program using 
 * the exit command.
 * 
 * 
 * pre: filename should be the name of a file in the same 
 *      folder as the program itself.
 * 
 */

ofstream open_output_file_stream(char *filename)
{
	ofstream *out = new (ofstream);
	
	out->open(filename);
	if (out->fail())
    {
		cout << "ERROR: Couldn't open "
			<< filename
			<< ", halting program!\n";
		exit (EXIT_FAILURE);
    }
	else
	{	
		cout << "Successfully opened "
			<< filename
			<< "!"
			<< endl;
	}
	// if we get to here, we successfully opened the file for writing
	return (*out);
}


//----------------- open_input_file_stream ---------------------
/* 
 * This function returns an object of type ifstream that gives the
 * user a way to read from the file filename. If filename
 * is not a valid file, then this function halts the program using 
 * the exit command.
 * 
 * 
 * pre: filename should be the name of a file in the same 
 *      folder as the program itself.
 * 
 */

ifstream open_input_file_stream(char *filename)
{
	ifstream *in = new (ifstream);
	
	in->open(filename);
	if (in->fail())
    {
		cout << "ERROR: Couldn't open "
			<< filename
			<< ", halting program!\n";
		exit (EXIT_FAILURE);
    }
	else
	{	
		cout << "Successfully opened "
			<< filename
			<< "!"
			<< endl;
	}
	
	// if we get to here, we successfully opened the file for writing
	return (*in);
}