How can I solve this "try/catch" problem?

[J.Killa]

So I'm somewhat new to programming and I have a assignment in which I have to verify if the numerator entered by the user is a decimal, instead of a integer. If it is, then I throw an exception...the thing is I don't really know how to do it because as you all know, it doesn't matter if the variable is integer, if I input 3.49...it will be shortened to 3. So how can I know if it was decimal?

int main()
{

int numerator,denominator;

try
{
cout << "Input the numerator : " ;
cin >> numerator;
cout << "Input the denominator : " ;
cin >> denominator;
if (denominator == 0)
throw denominator;
else
cout << numerator << '/' << denominador
<< "=" << double(numerator)/double(denominator) << endl;

}

catch(int e)
{
cout << " The value of the denominator " << e << " is invalid. " <<endl;
system("PAUSE");

}
return EXIT_SUCCESS;
}

[daviddoria]

You could input a string instead of an int and then check if the string contains a '.'.

[chary8088]

add a double type variable ldnumer , the variable receive a double type input
numerator 's value is transfered from ldnumer , if ldnumer is a integer, the ldnumer should be equal to numerator , else greater; see follow code:

int main()
{

int numerator,denominator;
double ldnumer = 0;

try
{
cout << "Input the numerator : " ;
cin >> ldnumer;
numerator = (int)ldnumer;//3.2->3 3.0->3  
cout << "Input the denominator : " ;
cin >> denominator;
if (denominator == 0 && numerator < ldnumer)//3.0 == 3 3.2 > 3
throw denominator;
else
cout << numerator << '/' << denominador
<< "=" << double(numerator)/double(denominator) << endl;

}

catch(int e)
{
cout << " The value of the denominator " << e << " is invalid. " <<endl;
system("PAUSE");

}
return EXIT_SUCCESS;
}

[J.Killa]

but I want to be able to catch the exception if the user inputs a decimal number and display it on screen...that's the exercise.

[chary8088]

Can't my code satisfy your requirement ???

[J.Killa]

your code is converting the decimal to integer. That's not the exercise. The exercise is to let the user do the input like decimal so that I can throw the error and catch it...like the denominator one.

[J.Killa]

ok...I just saw what you did...my bad...the problem is that the catch is integer...so that if you did would only work if both of them are wrong inputs.

EDIT: Well...thanks chary8088...i just modified it with what you gave me and it resulted:

int main()
{
 
int numerator,denominator;
double ldnumer = 0;
 
try
{
cout << "Input the numerator : " ;
cin >> ldnumer;
numerator = (int)ldnumer;//3.2->3 3.0->3  
if (numerator < ldnumer)
throw numerator;
cout << "Input the denominator : " ;
cin >> denominator;
if (denominator == 0)//3.0 == 3 3.2 > 3
throw denominator;
else
cout << numerator << '/' << denominator << "=" << double(numerator)/double(denominator) << endl;
 
}
catch (double a)
{
cout << " The value of the numerator " << a << " is invalid. " << endl;
system("PAUSE");
}
 
catch(int e)
{
cout << " The value of the denominator " << e << " is invalid. " <<endl;
system("PAUSE");
 
}
return EXIT_SUCCESS;
}

[chary8088]

I have revised the ,and can run normal ,which throw the exception

int main()
{ 
int numerator,denominator;
double ldnumer = 0; 
try
{
cout << "Input the numerator : " ;
cin >> ldnumer;
numerator = (int)ldnumer;//3.2->3 3.0->3  
cout << "Input the denominator : " ;
cin >> denominator;
if (denominator == 0 || numerator == ldnumer)//!!!!! revised
throw denominator;
else
cout << numerator << '/' << denominator<< "=" << double(numerator)/double(denominator) << endl; 
} 
catch(int e)
{cout << " The value of the denominator " << e << " is invalid. " <<endl;
system("PAUSE"); }
return EXIT_SUCCESS;
}

[chary8088]

I have test it , you also run the code
the code been revised which satisfy your want

[chary8088]

if the numerator entered by the user is a decimal, instead of a integer. If it is, then I throw an exception

That is if the numerator entered by the user is a decimal, then throw an exception
..

int main()
{ 
	while(1)
	{
	int numerator,denominator;
	double ldnumer = 0; 
	try
	{
		cout << "Input the numerator : " ;
		cin >> ldnumer;
		numerator = (int)ldnumer;//3.2->3 3.0->3  
		cout << "Input the denominator : " ;
		cin >> denominator;
		if(numerator < ldnumer)//3.0 == 3 3.2 > 3
			throw ldnumer;
		if (denominator == 0 ) 
			throw denominator;
		else
			cout << numerator << '/' << denominator<< "=" << double(numerator)/double(denominator) << endl; 
	} 
	catch(double e)
	{
		cout << " The value of the denominator " << e << " is invalid. " <<endl;
		system("PAUSE");
	}
	}
	return EXIT_SUCCESS;
}