overloading, scalar multiplication

toomanystars (151)
Hi Guys,

Need a little help. The issue is with the "operator*(Time& t)." I am trying to simply multiple a time object by a scalar double, in this case 3.0. However, I am not sure what's I am doing wrong as the compiler is not recognizing the operation
scalar=t1*scale. I suspect it has something to do with the constructor.

Thanks,

Mike

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class Time
{
public:
	Time();
	Time(int h, int m, int s);
	Time(double d);
	void input();
	void print()const;
	Time operator+(Time& t);
	Time operator-(Time& t);
	Time operator++();
	Time operator++(int);
	Time operator--();
	Time operator--(int);
	Time operator*(Time& t);
private:
	int hour, minutes, seconds;
};
int main()
{
	char choice;
	Time t1(1,1,1), t2(23,60,60), addition, subtraction, scalar;
	double scale=3.0;
	do
	{
		cout<<"\n\n";
		//t1.input();
		//t2.input();
		cout<<"Time 1 is: ";
		t1.print();
		cout<<"Time 2 is: ";
		t2.print();

		addition=t1+t2;
		cout<<"Addition yeilds: ";
		addition.print();
		cout<<endl;

		subtraction=t1-t2;
		cout<<"Subtraction yeilds: ";
		subtraction.print();

		scalar=t1*scale;////////problem here!!
		scalar.print();

		cout<<"Again (y/n): ";
		cin>>choice;
	}while(choice=='y');
	cout<<"Have a nice day!";
	exit(1);

	return 0;
	_getch();
}
Time::Time(){}
Time::Time(int h, int m, int s):hour(h), minutes(m), seconds(s){}
Time::Time(double d):hour(d),minutes(d),seconds(d){}
Time Time::operator*(Time& t)////////problem here!!
{
	int h=hour*t.hour;
	int m=minutes*t.minutes;
	int s=seconds*t.seconds;
	return Time(h,m,s);////////problem here!!
}
Time Time::operator--(int)
{
	--seconds;
	if(seconds<1){seconds=60;--minutes;}
	if(minutes<1){minutes=60;--hour;}
	return Time(hour,minutes,seconds);
}
Time Time::operator--()
{
	seconds--;
	if(seconds<1){seconds=60;minutes--;}
	if(minutes<1){minutes=60;hour--;}
	return Time(hour,minutes,seconds);
}
Time Time::operator++(int)
{
	++seconds;
	if(seconds>60){seconds=0;++minutes;}
	if(minutes>60){minutes=0;++hour;}
	return Time(hour,minutes,seconds);	
	
}
Time Time::operator++()
{
	seconds++;
	if(seconds>60){seconds=0;minutes++;}
	if(minutes>60){minutes=0;hour++;}
	return Time(hour,minutes,seconds);
}
Time Time::operator-(Time& t)
{
	int s=seconds-t.seconds;
	if(s<0){s=60+s;}

	int m=minutes-t.minutes;
	if(m<0){m=60+m;}
	
	int h=hour-t.hour;
	if(h<0){h=24+h;}

	return Time(h,m,s);
}
Time Time::operator+(Time& t)
{
	int h=hour+t.hour;
	int m=minutes+t.minutes;
	int s=seconds+t.seconds;

	if(s>60){m++;s=s%60;}
	if(m>60){h++;m=m%60;}
	return Time(h,m,s);
}
void Time::print()const
{
	(hour<10)?cout<<"0"<<hour<<":":cout<<hour<<":";
	(minutes<10)?cout<<"0"<<minutes<<":":cout<<minutes<<":";
	(seconds<10)?cout<<"0"<<seconds:cout<<seconds;
	(hour>0 && hour<12)?cout<<" am":cout<<" pm";
	cout<<endl;
}
void Time::input()
{
	char symbol;
	cout<<"Enter time in the following format 'hh:mm:ss: '";
	cin>>hour>>symbol>>minutes>>symbol>>seconds;
	while(symbol!=':' || hour<0 || minutes<0 || seconds<0 || hour>24 ||minutes>60 || seconds>60)
	{
		cout<<"Incorrect parameters, enter again: ";
		cin>>hour>>symbol>>minutes>>symbol>>seconds;
	}
	cout<<endl;
}
vkrishan (9)
see in line 15. You have defined operator* for your time class with argument also a time object pointer while you are calling the operator* with a double object which is not there.

If in your code you change in line 43 with t1=t1*t1 it works fine as suggested by my explanation above.

I tried your code with another operator* with argument double and return value Time and it compiled fine.
toomanystars (151)
Thanks for the help. I can't run the program now (don't have access to a compiler) but will try it later tonight.

Mike
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