Animal

//clang 3.8.0

#include <iostream>
#include <string>
#include <utility> //swap
#include <vector>
class Animal {
public:
    Animal() = default;
    Animal(const Animal &animal) = default;
    Animal(const std::string &name,
           const double weight,
           const double age,
           const std::string &ration):
    name(name), weight(weight), age(age), ration(ration) {};

    std::string getName() const {return this->name; };
    void setName(const std::string &name_) {this->name = name_;};


    Animal& operator=(const Animal &other) {
        Animal temp(other);
        swap(temp);
        return *this;
    }
    const bool operator<(const Animal &other) const {
        return this->name < other.name;
    }
   friend std::ostream& operator<<(std::ostream& os, const Animal& animal);
   friend std::istream& operator>>(std::istream& is, Animal& animal);

private:
    void swap(Animal &other) {
        std::swap(this->name, other.name);
        std::swap(this->weight, other.weight);
        std::swap(this->age, other.age);
        std::swap(this->ration, other.ration);
    }
    std::string name;
    double weight;
    double age;
    std::string ration;

};

std::ostream& operator<<(std::ostream& os, const Animal& a) {
    os << a.name << " " << a.age << " "  << a.weight << " " << a.ration;
    return os;
}
std::istream& operator>>(std::istream& is, Animal& a) {
    is >> a.name >> a.age >> a.weight >> a.ration;
    return is;
}
int main()
{
    std::vector <Animal> v;
    v.push_back({"tor", 12, 12, "d1"});
    v.push_back({"loki", 12, 12, "d2"});
    v.push_back({"set", 12, 12, "d2"});

    Animal animal;
    std::cin >> animal;
    v.push_back(animal);

    std::sort(v.begin(), v.end());
    for (const auto &a: v) std::cout << a << "\n";

}