Вывод на дисплей фамилий работников, чей стаж работы в организации превышает значение введенное с клавиатуры

#include <iostream>
#include <algorithm>
#include <string>
#include <ctime>
#include <functional>
#include <set>
#include <iterator>
 
class Worker {
    std::string _name;
    std::string _post;
    int _year;
public:
    Worker() : _name(""), _post(""), _year(0) {}
    Worker(const std::string & name, const std::string & post, int year) : _name(name),
    _post(post), _year(year) {}
    ~Worker() {}
    int year() const { return _year; }
    bool operator < (const Worker & w) const { return _name < w._name; }
    bool operator == (const Worker & w) const { return _name == w._name; }
    friend std::ostream & operator << (std::ostream & ost, const Worker & w) {
        ost << "\nName:\t" << w._name << "\nPost:\t" << w._post << "\nYear:\t" << w._year;
        return ost;
    }
};
 
class FindByStage : public std::unary_function<Worker, bool> {
    int _cur_year;
    int _min_stage;
public:
    FindByStage(int stage) : _min_stage(stage) {
        time_t tt = time(NULL);
        struct tm *pts;
        pts = localtime(&tt);
        _cur_year = pts->tm_year + 1900;
    }
    bool operator () (const Worker & w) {
        return _cur_year - w.year() > _min_stage;
    }
};
 
int main(){
    int num_workers;
    std::multiset<Worker> workers;
    std::string name, post;
    int year;
 
    std::cout << "Number of workers: ";
    std::cin >> num_workers;
    std::cin.get();
    while ( num_workers-- ){
        std::cout << "Name: ";
        std::getline(std::cin, name);
        std::cout << "Post: ";
        std::getline(std::cin, post);
        std::cout << "Year of employment: ";
        std::cin >> year;
        std::cin.get();
        workers.insert(Worker(name, post, year));
    }
 
    std::cout << "Minimum stage: ";
    std::cin >> year;
    FindByStage fbs(year);
    size_t cnt = std::count_if(workers.begin(), workers.end(), fbs);
    if ( ! cnt ) {
        std::cerr << "No workers with stage greater then " << year << std::endl;
        return 1;
    }
    std::cout << "Found " << cnt << " workers:" << std::endl;
    for ( std::multiset<Worker>::const_iterator i = workers.begin(); i != workers.end(); ++i )
        if ( fbs(*i) )
            std::cout << *i << std::endl;
 
    return 0;
}