why can't my program compile?

I'm trying to compile code from a book but it is having errors. here is the code:

Code:

// englio.cpp
// overloaded << and >> operators
#include <iostream>
using namespace std;
////////////////////////////////////////////////////////////////
class Distance                           //English Distance class
   {
   private:
      int feet;
      float inches;
   public:
      Distance() : feet(0), inches(0.0)  //constructor (no args)
         {  }
                                         //constructor (two args)
      Distance(int ft, float in) : feet(ft), inches(in)         
         {  }
      friend istream& operator >> (istream& s, Distance& d);  
      friend ostream& operator << (ostream& s, Distance& d);
   };
//--------------------------------------------------------------
istream& operator >> (istream& s, Distance& d)  //get Distance
   {                                            //from user
   cout << "\nEnter feet: ";  s >> d.feet;      //using
   cout << "Enter inches: ";  s >> d.inches;    //overloaded
   return s;                                    //>> operator
   }
//--------------------------------------------------------------
ostream& operator << (ostream& s, Distance& d)  //display
   {                                            //Distance
   s << d.feet << "\'-" << d.inches << '\"';    //using
   return s;                                    //overloaded
   }                                            //<< operator
////////////////////////////////////////////////////////////////
int main()
   {
   Distance dist1, dist2;          //define Distances
   Distance dist3(11, 6.25);       //define, initialize dist3

   cout << "\nEnter two Distance values:";
   cin >> dist1 >> dist2;          //get values from user
                                   //display distances
   cout << "\ndist1 = " << dist1 << "\ndist2 = " << dist2;
   cout << "\ndist3 = " << dist3 << endl;
   return 0;
   }

the errors are

(23) : error C2248: 'feet' : cannot access private member declared in class 'Distance'
(9) : see declaration of 'feet'
(24) : error C2248: 'inches' : cannot access private member declared in class 'Distance'
(10) : see declaration of 'inches'
(30) : error C2248: 'feet' : cannot access private member declared in class 'Distance'
(9) : see declaration of 'feet'
(30) : error C2248: 'inches' : cannot access private member declared in class 'Distance'
(10) : see declaration of 'inches'
(40) : error C2593: 'operator >>' is ambiguous
(42) : error C2593: 'operator <<' is ambiguous
(43) : error C2593: 'operator <<' is ambiguous

i'm using the microsoft visual c++ compiler. why are these errors coming up?

Your code compiles without errors or warnings for me on MSVC++ .NET 2003 and MSVC++ 6.0.

ok then I guess I have to enable or disable something in the compiler, but I have no idea what. can anyone help?

Try the following in MSVC++ 6.0 (if you are using .NET, let us know):

• Go to the File menu and select "New...".
• Make sure the Projects tab is selected.
• Set the Project name: Distances (or whatever you want)
• Set the Location: Whatever you want (e.g. C:\Tests\Distances)
• Select Win32 Console Application.
• Click OK.
• "An empty project" should be selected.
• Click Finish.
• Click OK.
• Go to the File menu and select "New..." again.
• Make sure the Files tab is selected.
• Check the box next to "Add to project:"
• Set the File name: englio.cpp
• Set the Location - leave the default location.
• Select C++ Source File.
• Click OK.
• Paste in code exactly as you posted it.
• Build the project by going to the Build menu and selecting "Build Distances.exe", or by hitting F7, or by clicking the Build button on the toolbar.

Does that work?

shoot, it didn't work. same errors.

Based on the errors, it doesn't seem to recognize the friend keyword, or the friend declaration and the definition aren't matching. Of course, in the code you posted, that is not the case, which is why it compiles for me. Are you sure the code you posted is exactly the same as the code you are compiling?

If that's the case, the only thing I can think of is a bad install, but that doesn't make any sense.

I had same question in VC++ , but ok in DEV-C++,
after read some source code from book, I find this is answer:

Code:

class Distance;      //adding prototype declare to remove this error.
istream& operator >> (istream& s, Distance& d);  
ostream& operator << (ostream& s, Distance& d);