Why does my program hangs?

[b1b2b3b4]

Can anyone please help? Whenever I input the first coordinate of x pt1, my program just hangs.

The code is below..

Shape

// shape.h
#include <string>
#ifndef SHAPE_H
#define SHAPE_H 1
using namespace std;

class Shape
{

	protected:
		int x, y;
		string name;
	public:
	// a simple inline constructor
	Shape(int new_x, int new_y, string new_name): x(new_x), y(new_y), name(new_name)
	{
		return;
	};
	
	virtual ~Shape()
	{
		return;
	};
	// inline getter/setter functions
	string getName() { return name; };
	void setName(string new_name)
	{
		name = new_name;
	}
	
	int getX() { return x; };
	void setX(int set_x)
	{
		x = set_x;
	}
	
	int getY() { return y; };
	void setY(int set_y)
	{
		y = set_y;
	}
	
	void toString();
};


#endif 

Square

// square.h
#ifndef SQUARE_H
#define SQUARE_H 1
#include <string>
#include "Shape.h"
using namespace std;

class Square : public Shape
{
    protected:
    int size;
    public:
    // a c'tor that calls the parent class's c'tor
    Square(int new_x, int new_y, string new_name): Shape(new_x, new_y, new_name)
    {
    	return;
    };
	
	void setXY();
	Square *arraySquare[1];
};

void Square::setXY()
{
	int count = 0;
	for(int i=0; i<4; i++)
	{
		cout<<"Please enter x-ordinate of pt. "<<i+1<<" : ";
		cin>>x;
		arraySquare[count]->setX(x);
		cout<<"Please enter y-ordinate of pt. "<<i+1<<" : ";
		cin>>y;
		arraySquare[count]->setY(y);
		count++;
	}
}

#endif  

Main

#include <iostream>
#include <string>
#include "Shape.h"
#include "Square.h"
using namespace std;

class Main
{
	public:
		void mainMenu();
		char menuChoice;
		void stringToUpper(string &s);
};

void stringToUpper(string &s)
{
   for(unsigned int l = 0; l < s.length(); l++)
  {
    s[l] = toupper(s[l]);
  }
}

void Main::mainMenu()
{
	cout<<"Welcome to Main program!"<<endl<<endl;
	cout<<"1)	Input data"<<endl;
	cout<<"2)	2"<<endl;
	cout<<"3)	3"<<endl;
	cout<<"4)	4"<<endl;
	cout<<"Q)	Enter 'Q' to quit"<<endl<<endl;
}

int main()
{
	char menuChoice;
	
	bool quit=false;
	Main main;
	Square *square;
	
	string shape, special;
	
	while ( !quit )
	{
		main.mainMenu();
		cout<<"Please enter your choice : ";
		cin>>menuChoice;
		menuChoice = toupper(menuChoice);
		
		switch(menuChoice)
		{
				case '1':
					cout<<endl<<"[ Input data ]"<<endl;
					cout<<"Please enter name of shape : "<<endl;
					cin>>shape;
					stringToUpper(shape);
					if(shape=="SQUARE")
					{
						square->setXY();
					}
					break;
				case '2':
					cout<<"Print"<<endl<<endl;
					break;	   	   	 
				case '3':
					cout<<"You choosen 3"<<endl<<endl;
					break;	 	 	 	 	 
				case '4':
					cout<<"You choosen 4"<<endl<<endl;
					break;
				case 'Q':
					cout<<"You have chosen to quit!"<<endl<<endl;
					quit=true;
					exit(0);	 	 	 	 
				default:
					cout<<"Invalid entry!"<<endl<<endl;
					break;
		}
	}
}

[cire]

class Square : public Shape
{
    protected:
    int size;
    public:
    // a c'tor that calls the parent class's c'tor
    Square(int new_x, int new_y, string new_name): Shape(new_x, new_y, new_name)
    {
    	return;
    };
	
	void setXY();
	Square *arraySquare[1];
};

void Square::setXY()
{
	int count = 0;
	for(int i=0; i<4; i++)
	{
		cout<<"Please enter x-ordinate of pt. "<<i+1<<" : ";
		cin>>x;
		arraySquare[count]->setX(x);
		cout<<"Please enter y-ordinate of pt. "<<i+1<<" : ";
		cin>>y;
		arraySquare[count]->setY(y);
		count++;
	}
}

So a Square has an array of one pointer to Square? This pointer is never initialized so it's pointing to some random place in memory. You then try to write to the memory it's pointing to. You then try to access it as if it is an array larger than one element, interpreting more random memory as a pointer to.. random memory, which you then try to write to.

That's a lot of bad mojo.

[b1b2b3b4]

It hangs also when my arraySquare is at [100]. Any idea how do I initialize or fix this?

[cire]

Well, the obvious thing would be to remove arraySquare from the Square class, since a square should not be a container of squares (or pointers to squares.)

Then, use a container.

[b1b2b3b4]

Could you please guide me and show me an example? I'm new to c++