Need help

[MKDWOLF]

I need some help with this program. When I'm trying to print the data to the screen, something weird happens.
also does anybody has any suggestions how to print just one class(in printOne function)?
THANK YOU

#include <iostream> 
#include "myHeader.h"
#include <stdlib.h>
#include <conio.h>
using namespace std;

//Function prototypes
void newData();
void printData();
void printOne();
void printAll();
void quit();


//global variables
bool showMenu = true;
const int NUMCLASSES = 10;
int NUMCLASSES2;
int iIndex;
int cData[NUMCLASSES];

int main()
{ 
     int function;
	
	//shows menu when showMenu is true.
	while(showMenu == true)
	{
		system("cls");
		cout << "==========================================" << endl;
		cout << " Class Planner " << endl;     //Prints data on screen
		cout << "==========================================" << endl;
		cout << " What do you want to do " << endl;
		cout << "1. Enter new data" << endl;
		cout << "2. Print data to screen" << endl;
		cout << "3. Exit" << endl;
		cout << "==========================================" << endl;
		cin>>function;

		switch(function)   //using switch to enter a function
		{
		case 1:
			{
				newData();
				break;
			}
		case 2:
			{
				printData();
				break;
			}
		case 3:
			{
				quit();
				break;
			}
		default:
			{
				break;
			}
		}


	}

	return 0;	
}
//quit function
void quit()
{
	char cQuit;
	
	system("cls");
	cout<<"Would you like to quit? (Y/N)\n";
	cin>>cQuit;

	if(cQuit == 'N' || cQuit == 'n')
	{
		system("cls");
	}
	else if(cQuit == 'Y' || cQuit == 'y')
	{
		system("cls");
		showMenu = false;
		cout<<"Please use this program again!"<<endl;
	}
	else
	{
		system("cls");
		quit();
	}

}
//asks the user to print new data
void newData()
{
	system("cls");
	cout<<"How many classes do you have? "; cin>>  NUMCLASSES2;
	
	cInfo cData[NUMCLASSES]; 
     //int iIndex; 
     for(iIndex = 0; iIndex < NUMCLASSES2; iIndex++)  
     {  
		   cout<<endl;
		   cin.ignore();
		   cout << "Class name: ";
		   cin.getline(cData[iIndex].className, NAMELENGTH);
           cout << "Class number: "; cin >> cData[iIndex].classNumber; 
           cin.ignore();
           cout << "Class meets on ('MWF' if it meet on Monday, Wednesday, and Friday): ";  
           cin.getline(cData[iIndex].classMeets, NAMELENGTH); 
           cout << "Start time: ";  cin >> cData[iIndex].classStart; 
           cout << "End time: ";  cin >> cData[iIndex].classEnd;
		   cin.ignore();
		   cout << "Teacher name: ";
		   cin.getline(cData[iIndex].teacherName, (NAMELENGTH));
		   cout << "Number of students: "; cin >> cData[iIndex].numberStudents;
		   cout << endl;
     }  
     for(iIndex = 0; iIndex < NUMCLASSES2; iIndex++) 
     {  
           cout << endl;
		   cout << "Class Name: " << cData[iIndex].className << endl; 
		   cout << "Class Number: " <<  cData[iIndex].classNumber << endl; 
           cout << "Class meets on: " << cData[iIndex].classMeets << endl; 
           cout << "Start Time: " << cData[iIndex].classStart << endl;
		   cout << "End Time: " << cData[iIndex].classEnd << endl;
		   cout << "Teacher: " << cData[iIndex].teacherName << endl;
		   cout << "Number of students: " << cData[iIndex].numberStudents << endl << endl;
     }
	 system("PAUSE");
     
	
}

void printData()
{
	cInfo cData[NUMCLASSES];
	int dataOption;
	
	system("cls");
	cout<<"Print Data to screen"<<endl;
	cout<<"1. Print All"<<endl;
	cout<<"2. Print a class"<<endl;
	cin>>dataOption;

	if(dataOption == 1)
	{
		system("cls");
		for(iIndex=0; iIndex < NUMCLASSES2; iIndex++)
		{
		
		cout <<  endl;
		cout << "Class Name: " << cData[iIndex].className << endl; 
		cout << "Class Number: " <<  cData[iIndex].classNumber << endl; 
        cout << "Class meets on: " << cData[iIndex].classMeets << endl; 
        cout << "Start Time: " << cData[iIndex].classStart << endl;
		cout << "End Time: " << cData[iIndex].classEnd << endl;
		cout << "Teacher: " << cData[iIndex].teacherName << endl;
		cout << "Number of students: " << cData[iIndex].numberStudents << endl << endl;
		}
		system("PAUSE");
	}
	else if(dataOption == 2)
	{
		system("cls");
	}
	else
	{
		printData();
	}
}

void printOne()
{
	system("cls");
}

 //(contents of the file myHeader.h)
#ifndef _MYHEADER_H
#define _MYHEADER_H

const int NAMELENGTH = 35;

struct cInfo
{
	char className[NAMELENGTH];
	int classNumber;
	char classMeets[NAMELENGTH];
	int classStart;
	int classEnd;
	char teacherName[NAMELENGTH];
	int numberStudents;
	
};
#endif

[Daved]

>> When I'm trying to print the data to the screen, something weird happens.
Can you be more specific?

>> does anybody has any suggestions how to print just one class(in printOne function)?
The same as in printData except don't use a for loop and only do one object?

[vart]

#include <stdlib.h>
it should be
#include <cstdlib>

#include <conio.h> - do not use it

	cout<<"How many classes do you have? "; cin>>  NUMCLASSES2;
	
	cInfo cData[NUMCLASSES];

You do not event check that NUMCLASSES2 is not greater than NUMCLASSES
Better use vector of structs of appropriate length

Try to avoid globas=ls - your usage of global array of int cData and local array of cInfo cData is confusing.

Calling regular var with UpperCase - is confusing as well

so - replace char arrays with std::string and arrays with std::vector
remove global variables

(and better remove system("cls") - users do not like, when the info from the screen just dissapears without a hint...

[MKDWOLF]

The printing error is becouse I'm declaring
cData[NUMCLASSES] twice;

"array in one function it doesn't populate the array in the other function."
So, how can I make the array a global variable?

[tabstop]

The printing error is becouse I'm declaring
cData[NUMCLASSES] twice;

"array in one function it doesn't populate the array in the other function."
So, how can I make the array a global variable?

The answer to the question you're literally asking is "declare it outside of any function (including main)". IOW: you already have a global variable named cData, so don't declare new ones in your functions because they will hide the global one.

HOWEVER, you don't actually want a global variable. You want to have an array in main (better yet -- a vector), and you want to pass that array (better yet -- a vector) into your functions.

[MKDWOLF]

HOWEVER, you don't actually want a global variable. You want to have an array in main (better yet -- a vector), and you want to pass that array (better yet -- a vector) into your functions.

And how I can do that??
I'm learning C++ for 4 months, so I need more info.

[Raigne]

#include <vector>
int some_func(std::vector<int>& my_intvector_ref);

int main()
{
  std::vector<int> test;
  some_func(test);
  return 0;
};

There are also tutorials on this site that tell you how to use them.

[MKDWOLF]

I'm pretty sure that I'm not supposed to use vectors(becouse I haven't learned about them yet). So, is any other way to make this program work.

I think that I should declare the array only once as a global variable. And I should use that array for adding and printing data.
But I don't know how to do that?

[tabstop]

I think that I should declare the array only once as a global variable. And I should use that array for adding and printing data.
But I don't know how to do that?

I don't know why you think that you "don't know how to do that", considering that's what you've already bloody done. Take out all definitions of cData that aren't the global one at the top of the code et voila.

If you ever feel the need to do it correctly (using non-global variables), then you'll want to look at passing parameters to functions.