Question

I am trying to complete my assignment.which says In a Distance class create an overloaded * operator so that two distances can be multiplied together. Here is my program:

#include<iostream>
using namespace std;
class distance
{
private:
    int a;
public:
    distance():a(10){}
    distance(int x)
    {
        a=x;
    }
    void print()
    {
    cout<<"\n a = "<<a<<" \n ";
    }
    distance operator *(distance);
};
distance distance :: operator *(distance d)
{
    a=a*d.a;
    return distance(a);
}
int main()
{
distance d1,d2,d3;
d1.print();
d2.print();
d3.print();
d3=d1 * d2;
d3.print();
return 0;
}

But I get a compilation error saying:

'distance' : ambiguous symbol.

when I run it on VC++

But it runs fine on Turbo C (by minor change: #include<iostream.h>).

Please explain where am I getting wrong. Thanks in advance.

Answer 1

There’s already a function called std::distance, which you’re bringing into scope through using namespace std and which clashes with your distance class.

Call your class something else (e.g. Distance) or, better yet, remove using namespace std.

P.S. This is a nice illustration of why using namespace X in this manner usually isn’t a good idea.