#include <iostream>
using namespace std;
#include <list>
#include <memory>
class OneDim{
public:
    int x;
    OneDim(int x):x(x){};
    OneDim operator +(OneDim &lhs);
    virtual void print(ostream &o)const;
};

OneDim OneDim::operator+(OneDim &r) {
    return OneDim(this->x+r.x);
}

void OneDim::print(ostream & o) const {
    o<<x;
}
ostream& operator<<(ostream &o,OneDim& x){
    x.print(o);
    return o;
}
class TwoDim:public OneDim{
public:
    int y;
    TwoDim(int x,int y):OneDim(x),y(y){};
    TwoDim operator+(TwoDim &r);
    void print(ostream &o)const;
};

TwoDim TwoDim::operator+(TwoDim &r) {
    return TwoDim(this->x+r.x, this->y+r.y);
}

void TwoDim::print(ostream &o) const {
    OneDim::print(o);
    o<<" "<<y;
}

class ThreeDim:public TwoDim{
public:
    int z;
    ThreeDim(int x,int y, int z):TwoDim(x,y),z(z){};
    ThreeDim operator+(ThreeDim &r);
    void print(ostream & o)const;
};

ThreeDim ThreeDim::operator+(ThreeDim &r) {
    return ThreeDim(this->x+r.x, this->y+r.y, this->z+r.z);
}

void ThreeDim::print(ostream &o) const {
    TwoDim::print(o);
    o<<" "<<z;
}

int main() {
    ThreeDim *p=new ThreeDim(1,2,3);
    list<unique_ptr<OneDim>> l;
    l.push_back(make_unique<OneDim>(5));
    l.push_back(make_unique<TwoDim>(6,3));
    l.push_back(make_unique<ThreeDim>(8,5,4));
    for(auto&x:l){
        cout<<*x;
    }
    return 0;
}