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Clock

nothing3 (23)
this is my mid term project. I think Ive got it down, but I was hoping some more experienced eyes could look over my code and offer any suggestions because I really need to get a good grade. It works as far as I can tell (i get no errors when compiled) but i tend to make a lot of stupid mistakes. even if you dont look over all of, any part you do look at for me would be helpful. thank you in advance.

the problem is:

a) Extend the definition of the class clockType by overloading the post-increment operator function as a member of the class clockType

b) write the definition of the function to overload the post nicrement operator for the class clockType as defined in part a


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#ifndef H_Clock
#define H_Clock

#include<iostream>

using namespace std;

class clockType
{
	friend ostream& operator << ( ostream&, const clockType& );
	
	friend istream& operator >> ( istream&, clockType& );

public:
	void setTime( int, int, int );
	void getTime( int&, int&, int& ) const;

	clockType operator++();

	clockType operator++( int );

	bool operator==( const clockType& ) const;
	bool operator!=( const clockType& ) const;
	bool operator<=( const clockType& ) const;
	bool operator<( const clockType& ) const;
	bool operator>=( const clockType& ) const;
	bool operator>( const clockType& ) const;

	clockType( int = 0, int = 0, int = 0 );

	int hr;
	int min;
	int sec;
};

#endif

ostream& operator << ( ostream& osObject, const clockType& timeOut)
{

	if ( timeOut.hr < 10 )
		osObject << "0";
	osObject << timeOut.hr << ":";

	if ( timeOut.min < 10 )
		osObject << "0";
	osObject << timeOut.min << ":";

	if ( timeOut.sec < 10 )
		osObject << "0";
	osObject << timeOut.sec << ":";

	return osObject;

}

istream& operator >> ( istream& isObject, clockType& timeIn )
{
	char ch;

	isObject >> timeIn.hr;
	isObject.get( ch );
	isObject >> timeIn.min;
	isObject.get( ch );
	isObject >> timeIn.sec;

	return isObject;

}

void clockType::setTime( int hours, int minutes, int seconds )
{
	if( 0 <= hours && hours <24 )
		hr = hours;
	else 
		hr = 0;
	if( 0 <= minutes && minutes <60 )
		min = minutes;
	else
		min = 0;
	if( 0 <= seconds && seconds <60 )
		sec = seconds;
	else 
		sec = 0;
}

void clockType::getTime( int& hours, int& minutes, int& seconds ) const
{
	hours = hr;
	minutes = min;
	seconds = sec;
}

clockType clockType::operator++()
{
	sec++;

	if( sec > 59 )
	{
		sec = 0;
		min++;

		if( min > 59 )
		{
			min = 0;
			hr++;

			if( hr > 23 )
				hr =  0;
		}
	}
	return*this;
}

clockType clockType::operator++( int )
{
	clockType clock( *this );

	sec++;

	if( sec > 59 )
	{
		sec = 0;
		min++;

		if( min > 59 )
		{
			min = 0;
			hr++;

			if( hr > 23 )
				hr =  0;
		}
	}
	return clock;
}

bool clockType::operator==( const clockType& otherClock ) const
{
	return( ( hr == otherClock.hr ) && ( min == otherClock.min ) && ( sec == otherClock.sec ) );
}

bool clockType::operator!=( const clockType& otherClock ) const
{
	return( ( hr == otherClock.hr ) || ( min == otherClock.min ) || ( sec == otherClock.sec ) );
}

bool clockType::operator<=( const clockType& otherClock ) const
{
	return( ( hr < otherClock.hr ) || 
		  ( ( hr == otherClock.hr ) && ( min < otherClock.min ) ) ||
		  ( ( hr == otherClock.hr ) && ( min == otherClock.min ) && 
		  ( sec <= otherClock.sec ) ) );
}

bool clockType::operator<( const clockType& otherClock ) const
{
	return( ( hr < otherClock.hr ) || 
		  ( ( hr == otherClock.hr ) && ( min < otherClock.min ) ) ||
		  ( ( hr == otherClock.hr ) && ( min == otherClock.min ) && 
		  ( sec < otherClock.sec ) ) );
}

bool clockType::operator>=( const clockType& otherClock ) const
{
	return( ( hr > otherClock.hr ) || 
		  ( ( hr == otherClock.hr ) && ( min > otherClock.min ) ) ||
		  ( ( hr == otherClock.hr ) && ( min == otherClock.min ) && 
		  ( sec >= otherClock.sec ) ) );
}

bool clockType::operator>( const clockType& otherClock ) const
{
	return( ( hr > otherClock.hr ) || 
		  ( ( hr == otherClock.hr ) && ( min > otherClock.min ) ) ||
		  ( ( hr == otherClock.hr ) && ( min == otherClock.min ) && 
		  ( sec > otherClock.sec ) ) );
}

clockType::clockType( int hours, int minutes, int seconds )
{
	setTime( hours, minutes, seconds );
}

int main()
{
	cout << "\n\n\tA Program to check the functionality"
		 << "\n\tof the class clockType" << endl;

	clockType myClock( 23, 45, 12 );
	clockType yourClock;

	char choice;

	cout << "\n\tMy Clock: " << myClock;

	cout << "\n\tEnter the hours, minutes and seconds of your clock";
	cin >> yourClock;

	do 
	{
		cout << "\n\n\t\t\tM E N U";
		cout << "\n\n\t Operation >\t: > ";
		cout << "\n\tOperation <\t: < ";
		cout << "\n\tOperation ==\t: == ";
		cout << "\n\tOperation !=\t: !";
		cout << "\n\tOperation >=\t: 1";
		cout << "\n\tOperation <=\t: 2";
		cout << "\n\tPre-Increment\t: 3";
		cout << "\n\tPost-Increment\t: 4";
		cout << "\n\tQuit\t: Q";

		cout << "\n\n\tPlease enter your choice: ";
			cin >> choice;

		if ( choice > 91 )
			choice -= 32;

		switch( choice )
		{
		case '>' : cout << "\n\tMy Clock > your clock is ";
			if ( myClock > yourClock )
				cout << "true";
			else
				cout << "false";
			break;

		case '<' : cout << "\n\tMy Clock < your clock is ";
			if( myClock < yourClock )
				cout << "true";
			else
				cout << "false";
			break;

		case '=' : cout << "\n\tMy Clock ==  your clock is";
			if( myClock == yourClock )
				cout << "True";
			else
				cout << "false";
			break;
		
		case '!' : cout << "\n\tMy Clock != your clock is";
			if( myClock != yourClock )
				cout << "true";
			else
				cout << "false";
			break;

		case '1' : cout << "\n\tMy Clock >= your clock is";
			if( myClock >= yourClock )
				cout << "true";
			else
				cout << "false";
			break;

		case '2' : cout << "\n\tMy Clock <= your clock is";
			if( myClock <= yourClock)
				cout << "true";
			else
				cout << "false";
			break;

		case '3' : cout << ++yourClock;
			cout << "-- Pre-incremented";
				break;

		case '4' : cout << yourClock++;
			cout << "- Post-incremented";
				break;
		}

	}while (choice != 'Q'); 

	cout << "\n\n\t";
	system( "pause" );
	return 0;
}
cire (8284)
Looks pretty good.

One caution: You chose to implement the class using the int type which can contain negative values and it's certainly possible to enter negative values in your program via the overloaded operator>>.

It doesn't matter in your program, but typically the prefix operator++ would return a reference and not a copy.

I think I would be inclined to implement the postfix operator++ like so:

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clockType clockType::operator++( int )
{
    clockType clock( *this );

    this->operator++() ;

    return clock;
}


so that any future changes to the implementation of the class would only require an update in the prefix operator++, and there isn't so much code duplication. The same goes for defining the relational operators in terms of other relational operators.
coder777 (8439)
for your ++ operator: instead of repeating the code put it in it's own function and call it from both operators. line 117 stays of course where it is.

your operator!= is wrong. Here's a little trick:
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bool clockType::operator!=( const clockType& otherClock ) const
{
	return ( ! operator==(otherClock) );
}
The same applies to the other comparison operators
Last edited on
nothing3 (23)
thank you!
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