Missing Constructor for Initialization - c++

Question

Hi I am trying to debug a program and one of the errors I am receiving is 'Missing Initialization for Constructor'. Do I need to declare the vector upfront and how do I initialize it?
#include <iostream>
#include <vector>
using namespace std;
class Point {
private:
double x;
double y;
public:
double get_x() { return x; }
double get_y() { return y; }
bool set_x(double arg) {
x = arg;
return true;
}
bool set_y(double arg) {
y = arg;
return true;
}
Point() : x(0), y(0) {}
Point(double argx, double argy) : x(argx), y(argy) {
}
};
class Vector {
private:
Point A;
Point B;
public:
Point get_A() { return A; }
Point get_B() { return B; }
Vector(const Point &arg1, const Point &arg2) : A(arg1), B(arg2)
{
//this->A = arg1;
//this->B = arg2;
//A = arg1;
//B = arg2;
}
void set_A(const Point &arg) {
A = arg;
}
void set_B(const Point &arg) {
B = arg;
}
static Vector add_vector(const Vector &vector1, const Vector &vector2) {
if (&vector1.B != &vector2.A) {
//Error 1 Vector V1 No Matching constructor for initialization for 'vector'
Vector rval;
return rval;
}
Point one = vector1.A;
Point two = vector2.B;
Vector newvector(one, two);
//newvector.A = one;
//newvector.B = two;
return newvector;
}
Vector add_vector(const Vector &arg) {
// Type of this? Vector *; These three lines are equivalent:
//Point one = this->A;
//Point one = (*this).A;
Point one = A;
Point two = arg.B;
Vector newvector(one, two);
//newvector.A = one;
//newvector.B = two;
return newvector;
}
};
int main() {
//Error 2 Vector v No Matching constructor for initialization for 'vector'
Vector v;
cout << "(" << v.get_A().get_x() << ", " << v.get_A().get_y() << "),\n" <<
"(" << v.get_B().get_x() << ", " << v.get_B().get_y() << ")\n";
//Error 3 Vector V1 No Matching constructor for initialization for 'vector'
Vector v1(1,2), v2(2,3);
Vector res = Vector::add_vector(v1, v2);
cout << "(" << res.get_A().get_x() << ", " << res.get_A().get_y() << "),\n" <<
"(" << res.get_B().get_x() << ", " << res.get_B().get_y() << ")\n";
}

Answer 1

Your issue here is your class is not default constructable.
Vector rval;
Requires a default constructor. Since you provided a user defined constructor the compiler will no longer make a default constructor for you.
To create a default constructor for Vector you can use
Vector() = default;
If you have C++11 or higher or you can use
Vector() {}
For pre C++11.
I am not sure what you are trying to do with
Vector v1(1,2)
Vector needs two Points and each Point needs 2 values.