inheritance problem

[soldier1984]

this program should be calculating the total and average from the given values by the user but it does not...what's wrong with this program???

#include <iostream>
#include <string>
using namespace std;
class stuPersonal
{
      protected:
                string name, rollno, sex;
                short age;
      public:
             stuPersonal(string n, string r, string s, short a)
             { name = n; rollno = r;
               sex = s; age = a; }
};
class stuMarks
{
      protected:
                double mark1, mark2, mark3, mark4;
      public:
             stuMarks() {}
             stuMarks(double m1, double m2, double m3, double m4)
             { mark1 = m1; mark2 = m2; mark3 = m3; mark4 = m4; }
};
class stuSports
{
      protected:
                double score;
};
class stuResult : public stuMarks, public stuSports
{
      protected:
                double total, avg;
                char grade;
      public:
             void totalnavg()
             { cout << "Total = " << mark1 + mark2 + mark3 + mark4 << endl;
               cout << "Average = " << (mark1 + mark2 + mark3 + mark4)/4 << endl; }
};
int main()
{
    string n, r, s; short a;
    double m1, m2, m3, m4;
    cout << "\n\tHELLO, THERE!\n"
         << "\nPlease fill in the following\n"
         << "   Name  : "; cin  >> n;
    cout << "Roll no. : "; cin  >> r;
    cout << "    Age  : "; cin  >> a;
    cout << "    Sex  : "; cin  >> s;
    stuPersonal personalobj(n,r,s,a);
    cout << endl << n << ", Please enter your marks:\n"
         << "Marks1 : "; cin  >> m1;
    cout << "Marks2 : "; cin  >> m2;
    cout << "Marks3 : "; cin  >> m3;
    cout << "Marks4 : "; cin  >> m4;
    stuMarks marksobj(m1,m2,m3,m4);
    stuResult resultobj;
    resultobj.totalnavg();
    system("pause");
}

[AbstractionAnon]

Line 55: You instantiate resultobj, but you don't initialize it. What do you think mark1-4 contain?

This should be:

    stuResult resultobj (marksobj);

This implies that stuResult has a constructor that accepts a stuMarks object.

PLEASE USE CODE TAGS (the <> formatting button) when posting code.
It makes it easier to read your code and also easier to respond to your post.
http://www.cplusplus.com/articles/jEywvCM9/

[soldier1984]

i added in class stuResult this:

stuResult(stuMarks) {}

and i changed line 55 to be:
stuResult resultobj (marksobj);

but still it doesn't work...it keeps printing garbage values as results.

[AbstractionAnon]

Your added constructor does nothing. You still have not initialized the members of the inherited class.

Proper constructor:

    stuResults (const StuMarks & marks) : stuMarks (marks)     
    {}

Note the underlined portion. This calls the constructor of the inherited class.

[soldier1984]

it worked...thanks a lot for your help.