How to use TWO objects and use of *this pointer with operator over loading

[Mubeshier]

This programe is made for biggners in c++ to made programe efficently and hide your prevate data form the user of your programe.This programe is made with the use of this pointer and also use the operator overloading. I will share this programme with others to understand it.

//this programme will gives the addition,subtraction,multiplication and division with reduce fraction
//and it also tells u to select your own choice
#include<iostream>
#include<conio.h>
using namespace std;
class fraction
{
    private://class attributes
        int num;
        int denum;
    public://class behaviors
        fraction()//constructor without parameters
        {
            num=denum=1;
        }
        fraction(int n,int m)//constructor with parameters
        {
            num=m;
            denum=m;
        }
        void setnum (int );
        int getnum();
        void setdenum(int  );
        int getdenum();
        //fraction add(fraction );
        // word operator is pre-defined
        fraction operator +(fraction );//operator overloadin for addition
        //fraction sub(fraction );
        fraction operator -(fraction );//operator overloading for subtraction
        //fraction multi(fraction );
        fraction operator *(fraction );//operator overloading for multiplication
        //fraction div(fraction );
        fraction operator /(fraction );//operator overloading for division
        fraction display();//use to display the values
        fraction reduce();//use to reduce the fraction
};
fraction result;//class object to save the result of numerator and dunumenator and to separate the data from the parameter's data which we pass to the
// ...functions
void fraction::setnum(int n)//set the value of numenator
{
    num=n;
}
void fraction::setdenum(int m)//set value of denumenator
{
    denum=m;
}
int fraction::getnum()//get the value of the numenator
{
    return num;
}
int fraction::getdenum()//get the value of denumenator
{
    return denum;
}
fraction fraction::operator +(fraction b)//the formula applied here on fractions a/b + c/d to solve them.
                                        //The formula is  ad + bc/bd
{
    //fraction result;
    result.num=(num*b.denum)+(b.num*denum);
    result.denum=denum*b.denum; 
}
fraction fraction::operator -(fraction b)//subtraction of fractions 
{
    result.num=(num*b.denum)-(b.num*denum);
    result.denum=denum*b.denum;
}
fraction fraction::operator *(fraction b)//multiplication of fractions 
{
    result.num=(num*b.num);
    result.denum=denum*b.denum;
}
fraction fraction::operator /(fraction b)//division of fraction is 
{
    result.num=(num*b.denum);
    result.denum=denum*b.num;
}
fraction fraction::reduce()//here is the algo to reduce the resultant fraction and to check whether the fraction is reducable or not
{
    //if(result.num>result.denum)
    {
        int small=result.denum;
        for(int i=small;i>0;i--)
        {
            if((result.num%i==0)&&(result.denum%i==0))
            {
                result.num/=i;
                result.denum/=i;
                //cout<<"\nReduced fraction is "<<reducenum<<"/"<<reducedenum<<endl;
            }

        }
        cout<<"\a\nReduced fraction is "<<result.num<<"/"<<result.denum<<endl;
    }
}
fraction fraction::display()
{
    int count=0;    
    for(int i=2;i<=100;i++)
    { 
        if(result.num%i==0)
        {
            if(result.denum%i==0)
            {
                count++;
                //cout<<"Fraction is reducable by  :"<<i<<endl;
            }
        }
    }

    if(count>=1)
    {
        cout<<"\aFraction is reducable   \n";
        cout<<result.num<<"/"<<result.denum<<"\n";
    }
    else
    {
        cout<<"\aFraction is not reducable  \n";
        cout<<result.num<<"/"<<result.denum<<"\n";
    }
}
int main()
{
    int a,b,c,d,x;
    fraction f1=fraction();
    fraction f2=fraction();
    cout<<"********************************************************************************"<<endl;
    //cout<<"Enter only positive intigers\n";
    cout<<"\tFraction 1:\n";
    cout<<"\aEnter numenator  ";
    cin>>a;
    cout<<"\aEnter denumenator  ";
    cin>>b;
    cout<<"\tFraction  2:\n";
    cout<<"\aEnter numenator  ";
    cin>>c;
    cout<<"\aEnter denumenator  ";
    cin>>d;
    cout<<"********************************************************************************"<<endl;
    f1.setnum(a);
    f1.setdenum(b);
    f2.setnum(c);
    f2.setdenum(d);
    cout<<"\aIf you need Addition of fraction Enter :1 "<<endl;
    cout<<"If you need Subtraction of fractions Enter :2\n";
    cout<<"If you need Multiplication of fractions Enter :3\n";
    cout<<"If you need Division of fractions Enter :4\n";
    cin>>x;
    cout<<"********************************************************************************\n";
        if(x==1)
        {
            cout<<"  Addition\n";
            //f1.add(f2);
            f1+f2;
            f2.display();
            f2.reduce();
        }
        if(x==2)
        {
            cout<<"  Subtraction\n";
            //f1.sub(f2);
            f1-f2;
            f2.display();
            f2.reduce();
        }
        if(x==3)
        {
            cout<<"  Multiplication\n";
            //f1.multi(f2);
            f1*f2;
            f2.display();
            f2.reduce();
        }
        if(x==4)
        {
            cout<<"  Division\n";
            //f1.div(f2);
            f1/f2;
            f2.display();
            f2.reduce();
        }
    return 0;
}

[rubberman]

There are a number of issues with your post, starting with initializing member variables inside the body of the constructor instead of in the initializer list. Try, try again!

[Mubeshier]

No, this progamme is properly working and there is no problem in my constructor.

[rubberman]

Just because code works doesn't mean it is well written! I used to teach advanced C++ programming classes to our engineers from all over the world and covered these issues in depth.
Here is how your constructors should be:

public:
fraction() : num(1), denum(1)
{}
fraction(int n,int m) : num(n), denum(m)
{}

Note the error in your constructor with arguments where you set both num, and denum with the argument n. I assume you meant to set denum to argument m.