Exception Handling (Integer) in C++

#include<iostream>
#include<math.h>
#include<conio.h>
using namespace std;
main()
{
int n,j;
A:
cout<<"\nEnter Number:";
cin>>n;
try
{
if(n<0)
throw(n);
else
cout<<pow(n,3);
}
catch(int a)
{
cout<<"Negative Number Can't be taken.:";
cout<<"\nPress any Key to Enter Again:";
getch();
goto A;
}

}