#include <vector>

// abstract base class (interface) for AnalyzedObject
class AnalyzedObject {
public:
    AnalyzedObject() {}
    virtual ~AnalyzedObject() {}

    // provide getters for all the things an evaluator may consider
    virtual bool Do_you_support_key_feature_one() const = 0;
    virtual bool Do_you_support_key_feature_two() const = 0;
    virtual int YearsService() const = 0;
    virtual int Price() const = 0;
};

// abstract base class (interface) for voter/evaluator
class Evaluator {
public:
    Evaluator();
    virtual ~Evaluator() {}
    virtual bool vote(const AnalyzedObject&) = 0;
};

// raw pointers here is ill-advised
typedef std::vector<Evaluator*> voter_panel_type;

// abstract base class (interface) for voting policy
class VotingPolicy {
public:
    VotingPolicy();
    virtual ~VotingPolicy() {}
    virtual bool vote(voter_panel_type, const AnalyzedObject&) = 0;
};

// implement a voting policy
class MajorityRules : public VotingPolicy {
    bool vote(std::vector<Evaluator*> evaluators, const AnalyzedObject &object) {
        voter_panel_type::size_type yes = 0;
        for (auto voter : evaluators) {
            if (voter->vote(object))
                yes += 1;
        }
        return yes * 2 > evaluators.size();
    }
};