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Problem with inheritance in C++

cpp123 (16)
Here's the code:
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//gradedactivity.h 
class gradedactivity 
{
 public:
  char letter;
  void func();
  char getLetter()
    {
      return letter;
    }

};


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//gradedactivity.cpp
#include "gradedactivity.h"
#include <iostream>
using namespace std;

void gradedactivity::func()
{
  cout << "This is func function of gradedactivity" <<endl;
  
}


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//passfailactivity.h
#include "gradedactivity.h"
class passfailactivity : public gradedactivity {
 public:
  float passingscore;
  void func(int);
  void msg();
  
};



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//passfailactivity.cpp

#include "passfailactivity.h"
#include <iostream>
using namespace std;
void passfailactivity::msg()

{


  cout << "In msg of passfailactivity" <<endl;


}


void passfailactivity::func(int j)
{
cout << "This is func function of passfailactivity" <<endl;

}


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//prog.cpp
#include "passfailactivity.h"
#include <iostream>
using namespace std;

int main()
{
  passfailactivity e;

  e.msg();

    e.func(6);
    e.func();
  return 0;
}


I get this result on Linux:

webdev:~/cppcode$ g++ -c passfailactivity.cpp
webdev:~/cppcode$ g++ -c gradedactivity.cpp
webdev:~/cppcode$ g++ -c prog.cpp
prog.cpp: In function `int main()':
prog.cpp:12: no matching function for call to `passfailactivity::func()'
passfailactivity.h:5: candidates are: void passfailactivity::func(int)
webdev:~/cppcode$

My question is isn't void func() inherited by passfailactivity ? Why do I get this error ?
Any help would be welcome.
Thanks!
firedraco (6243)
That is because the function is being "hidden". Read this for information:

http://www.parashift.com/c++-faq-lite/strange-inheritance.html#faq-23.9
cpp123 (16)
Thanks a lot !!
Looks like, coming in from the Java world, I am in for quite a lot of surprise !!

In java this kind of thing would be perfectly acceptable and would run just fine with no "using" like declarations in the derived class !

And also , in Java , hiding applies to static methods (not sure how C++ handles static methods with same signature in base and derived classes) and fields.
firedraco (6243)
Probably hides them too. If you want to do something like overloading through classes like you seem to, you would have to use virtual functions.
vijaysaluru (23)
Right and if you consciously want to call base func() then easy way is to redefine base method in derived class by:
1) simply call base method using scope resolution operator => gradedactivity::func();
2) or simply __super::func(); //super is a keyword (this will also work for multi-level inheritance)
guestgulkan (2942)
__super keyword is Microsoft specific.
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