#include <iostream>
using namespace std;
class Distance
{
protected:

public:
    int feet;
    float inches;
    Distance()
    {
        feet=0;
        inches=0.0;
    }
    Distance(int ft, float inc )
    {
        feet=ft;
        inches=inc;
    }

    void get_distance()
    {
        cout << "write feets: \n";
        cin >> feet;
        cout << "write inches: \n";
        cin >> inches;
    }

    void show_distance()
    {
        cout << feet << "\'" << inches << '\"'<<endl;
    }

    ~Distance() {}
};

class SubClass:public Distance
{
private:

public:
    Distance operator+(Distance d2) const
    {
        int f = feet + d2.feet;
        float i = inches + d2.inches;
        if (i >=12.0){
            i -= 12.0;
            f++;
        }
        return Distance(f,i);
    }

    Distance operator-(Distance d2) const
    {
        if ( (d2.feet>feet) || ( (d2.feet==feet) && (d2.inches>inches) ) ){
            cout<<"subtraction is not possible"<<endl;
            return Distance(0,0);
        }
        else
        {
            int f = feet - d2.feet;
            float i=0;
            if (d2.inches > inches){
                i += 12.0;
                f--;
            }
            i  = i+inches - d2.inches;
            return Distance(f,i);
        }
    }

    Distance operator*(int a)
    {
        inches=inches*a;
        feet=feet*a;
        while(inches>=12){
            inches -= 12.0;
            feet++;
        }
        return Distance(feet,inches);
    }

    Distance operator/(int a)
    {
        inches=inches+feet*12;
        feet=0;
        inches=inches/2;
        while(inches>=12){
            inches -= 12.0;
            feet++;
        }
        return Distance(feet,inches);
    }

    void operator+=(Distance d2)
    {
        feet += d2.feet;
        inches += d2.inches;
        if (inches >=12.0){
            inches -= 12.0;
            feet++;
        }
    }

    void operator-=(Distance d2)
    {
        if ((d2.feet>feet) || ((d2.feet==feet)&&(d2.inches>inches))){
            cout<<"subtraction is not possible"<<endl;
        }
        else
        {
            feet -= d2.feet;
            if (inches<d2.inches){
                feet--;
                inches+=12;
            }
            inches -= d2.inches;
        }
    }

    void operator*=(int a)
    {
        inches=inches*a;
        feet=feet*a;
        if(inches>=12){
            inches -= 12.0;
            feet++;
        }
    }

    void operator/=(int a)
    {
        inches=inches+feet*12;
        feet=0;
        inches=inches/2;
        while(inches>=12){
            inches -= 12.0;
            feet++;
        }
    }

    bool operator<( Distance d2 )
    {
        float bf1 = feet + inches / 12;
        float bf2 = d2.feet + d2.feet / 12;
        return (bf1 < bf2) ? true : false;
    }

    bool operator>( Distance d2 )
    {
        float bf1 = feet + inches / 12;
        float bf2 = d2.feet + d2.feet / 12;
        return (bf1 > bf2) ? true : false;
    }

    bool operator<=( Distance d2 )
    {
        float bf1 = feet + inches / 12;
        float bf2 = d2.feet + d2.feet / 12;
        return (bf1 <= bf2) ? true : false;
    }

    bool operator>=( Distance d2 )
    {
        float bf1 = feet + inches / 12;
        float bf2 = d2.feet + d2.feet / 12;
        return (bf1 >= bf2) ? true : false;
    }

    bool operator==( Distance d2 )
    {
        float bf1 = feet + inches / 12;
        float bf2 = d2.feet + d2.feet / 12;
        return (bf1 == bf2) ? true : false;
    }

    bool operator!=( Distance d2 )
    {
        float bf1 = feet + inches / 12;
        float bf2 = d2.feet + d2.feet / 12;
        return (bf1 != bf2) ? true : false;
    }
};
int main()
{
    SubClass x;
    SubClass y;

    x.get_distance();
    x.show_distance();
    y.get_distance();
    y.show_distance();
    x-=y;
    x.show_distance();

    return 0;
}