Mega Code Archive
Overload prefix ++ for Point
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#include <iostream>
using namespace std;
class Point {
int x, y;
public:
Point() {} // needed to construct temporaries
Point(int px, int py) {
x = px;
y = py;
}
void show() {
cout << x << " ";
cout << y << "\n";
}
Point operator+(Point op2);
Point operator-(Point op2);
Point operator=(Point op2);
Point operator++();
};
// Overload + for Point.
Point Point::operator+(Point op2)
{
Point temp;
temp.x = op2.x + x;
temp.y = op2.y + y;
return temp;
}
// Overload - for Point.
Point Point::operator-(Point op2)
{
Point temp;
// notice order of operands
temp.x = x - op2.x;
temp.y = y - op2.y;
return temp;
}
// Overload asignment for Point.
Point Point::operator=(Point op2)
{
x = op2.x;
y = op2.y;
return *this; // i.e., return object that generated call
}
// Overload prefix ++ for Point.
Point Point::operator++()
{
x++;
y++;
return *this;
}
int main()
{
Point ob1(10, 20), ob2( 5, 30), ob3(90, 90);
ob1.show();
ob2.show();
++ob1;
ob1.show(); // displays 11 21
ob2 = ++ob1;
ob1.show(); // displays 12 22
ob2.show(); // displays 12 22
ob1 = ob2 = ob3; // multiple assignment
ob1.show(); // displays 90 90
ob2.show(); // displays 90 90
return 0;
}
10 20
5 30
11 21
12 22
90 90
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