ошибка LNK2019

#include <string>
#include <list>
 
class Animals{
private:
    std::string _type;//TODO: add prefixes
    std::string _name;
    std::string _voice;
    double _weight;
    bool _health;
public:
    std::string getType() const;//TODO: add const for methods that doesn't change class state
    std::string getName() const;
    std::string getVoice() const;
    double getWeight() const;
    bool getHealth() const;
    void setType(std::string type);
    void setName(std::string name);
    void setVoice(std::string voice);
    void setWeigt(double weight);
    void setHealth(bool health);
    void operator()(std::list<Animals> &myList);
    std::string toString();
    Animals();
    Animals(std::string type, std::string name, std::string voice, double weight, bool health);
    //~Animals();
};
 
#include "stdafx.h"
#include "Animals.h"
#include <string>
#include <algorithm>
#include <cstdlib>
 
Animals::Animals(std::string type, std::string name, std::string voice, double weight, bool health){
    Animals::_type = type;
    Animals::_name = name;
    Animals::_voice = voice;
    Animals::_weight = weight;
    Animals::_health = health;
}
 
std::string Animals::getType() const{
    return _type;
}
std::string Animals::getName() const{
    return _name;
}
std::string Animals::getVoice() const{
    return _voice;
}
double Animals::getWeight() const{
    return _weight;
}
 
bool Animals::getHealth() const{
    return _health;
}
void Animals::setType(std::string type){
    Animals::_type = type;
}
void Animals::setName(std::string name){
    Animals::_name = name;
}
void Animals::setVoice(std::string voice){
    Animals::_voice = voice;
}
void Animals::setWeigt(double weight){
    Animals::_weight = weight;
}
 
void Animals::setHealth(bool health){
    Animals::_health = health;
}
void Animals::operator()(std::list<Animals> &myList){
    stable_sort(myList.begin(), myList.end(), [](Animals a, Animals b){
        return a.getWeight() < b.getWeight();
    });
}
std::string Animals::toString(){
    return _type + " " + _name + " " + _voice + " " + std::to_string(_weight);
}
 
// Farm2.cpp : Defines the entry point for the console application.
//
 
#include "stdafx.h"
#include "Animals.h"
#include <list>
#include <iostream>
#include <algorithm>
#include <cstdlib>
 
 
int _tmain(int argc, _TCHAR* argv[])
{
    std::list<Animals> myList;
    myList.push_back(Animals("Chicken", "Bob", "kukareky", 100, true));
    myList.push_back(Animals("Chicken", "Ted", "kukareky", 110, true));
    myList.push_back(Animals("Pig", "Gerg", "xruxru", 1500, true));
    myList.push_back(Animals("Turkey", "Pol", "IDontKnow", 300, true));
    myList.push_back(Animals("Turkey", "Mildi", "IDontKnow", 350, true));
 
    //print list
    for (std::list<Animals>::iterator it = myList.begin(); it != myList.end(); ++it){
        std::cout << ' ' << ((Animals)*it).toString() << std::endl;
    }
 
    //sort
    stable_sort(myList.begin(), myList.end(), [](const Animals a, const Animals b){//pass a and b as const ref.
        return a.getName() < b.getName();
    });
 
    //print list
    for (std::list<Animals>::iterator it = myList.begin(); it != myList.end(); ++it){
        std::cout << ' ' << ((Animals)*it).toString() << std::endl;
    }
 
    //functor
    Animals buf;
    buf(myList);
 
    //print list
    for (std::list<Animals>::iterator it = myList.begin(); it != myList.end(); ++it){
        std::cout << ' ' << ((Animals)*it).toString() << std::endl;
    }
 
    //all_of
    std::cout << "all health : " << all_of(myList.begin(), myList.end(), [](const Animals a){return a.getHealth(); }) << std::endl;
    system("pause");
    return 0;
}

Animals() = default;

Animals(){}