Exceptions

[CurtisBridges]

Exceptions
I am working on a class project as layed out by the instructor. This is in conjunction with Chapter 13 (Exceptions) from the book How To Program in C++ by Deitle 4/e. I am at a total loss on this subject. I thought that catching problems was up to the compiler. I have included Figure 13.1 for an example as per instructions and some code I have been working on. Could someone please look this over and help me get my brain around exceptions or at least this project?

// Fig. 13.1: fig13_01.cpp
// A simple exception-handling example that checks for
// divide-by-zero exceptions.
Code: 
#include <iostream>using std::cout;using std::cin;using std::endl;#include <exception>using std::exception;// DivideByZeroException objects should be thrown by functions// upon detecting division-by-zero exceptionsclass DivideByZeroException : public exception {public:   // constructor specifies default error message   DivideByZeroException::DivideByZeroException()      : exception( "attempted to divide by zero" ) {}};  // end class DivideByZeroException// perform division and throw DivideByZeroException object if // divide-by-zero exception occursdouble quotient( int numerator, int denominator ){   // throw DivideByZeroException if trying to divide by zero   if ( denominator == 0 )      throw DivideByZeroException(); // terminate function   // return division result   return static_cast< double >( numerator ) / denominator;}  // end function quotientint main(){   int number1;    // user-specified numerator   int number2;    // user-specified denominator   double result;  // result of division   cout << "Enter two integers (end-of-file to end): ";   // enable user to enter two integers to divide   while ( cin >> number1 >> number2 ) {         // try block contains code that might throw exception      // and code that should not execute if an exception occurs      try {         result = quotient( number1, number2 );         cout << "The quotient is: " << result << endl;      } // end try      // exception handler handles a divide-by-zero exception      catch ( DivideByZeroException &divideByZeroException ) {         cout << "Exception occurred: " <<             divideByZeroException.what() << endl;      } // end catch      cout << "\nEnter two integers (end-of-file to end): ";   }  // end while   cout << endl;   return 0;  // terminate normally}  // end main

Here is the instructions and code I'm trying to use.

/*Create a program that defines three user defined exception classes
(called ExceptionOne, ExceptionTwo, and ExceptionThree
- with the messages being the same as the name - see Figure 13.1 for an example).
The program should have a loop with a menu with four selections
- Option 1 will throw ExceptionOne, Option 2 ExceptionTwo, Option 3 ExceptionThree
, and Option 4 to exit.
The catch block should only catch the first two exceptions explicitly
with the last exception caught generically.
Make sure the switch logic is inside a try block followed by three catch blocks.
///////////////////////////////////////////////////////////////////////////////*/
Code: 
#include <iostream>#include <exception>#include <ctime>using std::cout;using std::cin;using std::endl;class BaseException {public:   // constructor specifies default error message	ExceptionOne::BaseException ()	 : ExceptionOne }// end class class ExceptionOne: public BaseException {public:	ExceptionOne::ExceptionOne()		:ExceptionOne}// end classclass ExceptionTwo: public ExceptionOne {public:   // constructor specifies default error message  ExceptionTwo::ExceptionTwo()	  : ExceptionTwo}  // end class class ExceptionThree: public ExceptionTwo {public:	ExceptionThree::ExceptionThree()		:ExceptionThree}// end classint main(){

Any help greatly appreciated. Thanks

[Salem]

Perhaps learn how to use code-tags as well.

[Dani]

Um ... yeah, that's readable. :( Perhaps you could repost your code using line breaks?