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Curtis Bridges 6Feb2007 23:25

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.

#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 exceptions
class DivideByZeroException : public exception {


  // constructor specifies default error message
      : exception( "attempted to divide by zero" ) {}

};  // end class DivideByZeroException

// perform division and throw DivideByZeroException object if
// divide-by-zero exception occurs
double 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 quotient

int 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.

#include <iostream>

#include <exception>

#include <ctime>

using std::cout;
using std::cin;
using std::endl;

class BaseException


  // constructor specifies default error message
        ExceptionOne::BaseException ()
        : ExceptionOne

 }// end class
class ExceptionOne: public BaseException {



}// end class

class ExceptionTwo: public ExceptionOne {


  // constructor specifies default error message
          : ExceptionTwo

}  // end class

class ExceptionThree: public ExceptionTwo {



}// end class

int main()

Any help greatly appreciated. Thanks

DaWei 7Feb2007 17:36

Re: Exceptions
Why would you post the same question 3 times? To dilute your response? Because you don't even know enough to know where it goes? Because you haven't read the "Before you make a query" thread or any other "How to Post....." thread in the whole wide world? I don't even want to read your question. I will respond: do your own homework.

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