Перегрузка функций и операторов, почему программа не работает? - C++ - Ответ 4740518

#include <iostream>
using namespace std;
class Coord
{public:
int x;
int y;
    Coord()
    {cout<<"Input x: \n";
    cin>>x;
    cout<<"Input y: \n";
    cin>>y;
    }
    void out()
    {cout<<"x is: "<<x<<"\n";
    cout<<"y is: "<<y<<"\n";
    }
    bool operator!=(Coord &ob);
    bool operator==(Coord &ob);
    friend Coord operator+(Coord ob1, int ch);
    friend Coord operator-(Coord ob1, Coord ob2);
    friend Coord operator-(Coord ob1, int ch);
};
Coord operator+(Coord ob1, Coord ob2)
{Coord ob;
ob.x = ob1.x + ob2.x;
ob.y = ob1.y + ob2.y;
return ob;} 
Coord operator+(Coord ob0, int ch)
{Coord ob1;
ob1.x = ob0.x + ch;
ob1.y = ob0.y + ch;
return ob1;}
Coord operator-(Coord ob1, Coord ob2)
{Coord ob;
ob.x = ob1.x - ob2.x;
ob.y = ob1.y - ob2.y;
return ob;}
Coord operator-(Coord ob1, int ch)
{Coord ob;
ob.x = ob1.x - ch;
ob.y = ob1.y - ch;
return ob;}
bool Coord::
operator==(Coord &ob)
{return  ((x == ob.x)&&(y == ob.y));}
bool Coord::
operator != (Coord &ob)
{return ((x != ob.x)||(y != ob.y));}
int main()
{Coord obj1;
Coord obj2;
if (obj1 != obj2) cout<<"obj1 ne raven obj2 \n";
else cout<<"obj1 ravno obj2 \n";
obj1 = obj2;
cout<<"obj1 and obj2 getting equal... \n";
if (obj1 == obj2) cout<<"Obj1 raven Obj2 \n";
else cout<<"Obj1 ne ravno Obj2 \n";
Coord obj3 = obj1+obj2;
cout<<"Summa Obj1 i Obj2 ravna: \n";
obj3 = obj1+obj2;
obj3.out();
int k;
cout<<"Vvedite chislo kotoroe budet priplusovanno k Obj1: ";
cin>>k;
cout<<'\n';
obj3 = obj1+k;
obj3.out();
Coord obj4 = obj2-obj1;
cout<<"obj2 - Obj1 = \n";
obj4.out();
cout<<"Vvedite chislo kotoroe budet otnyato ot Obj2: ";
cin>>k;
cout<<'\n';
obj4 = obj2 - k;
obj4.out();
cin.get();
cin.get();
}