#include "test_runner.h"

#include <numeric>
#include <iostream>
#include <vector>
#include <string>
using namespace std;

template <typename Iter >
class Page {
private:
    Iter first , last;
public:
    Page(Iter f, Iter l) : first(f) , last(l) { }
    Iter begin() const { return first;}
    Iter end() const {return last;}
    size_t size() {return last-first;}
};


// Реализуйте шаблон класса Paginator

template <typename Iterator>
class Paginator {
public:
    Paginator(Iterator begin,Iterator end,size_t page_size){
        if(begin==end){
            _page_count=0;
            _pages.push_back({begin, end});
        }else{
            _page_count=0;
            size_t pagen = end - begin;
            auto begin_p = begin;
            while((end-begin_p)>pagen){
                _pages.push_back({begin_p,begin_p+4});
                begin_p+=4;
                _page_count++;
            }
            _pages.push_back({begin_p,end});

        }
    }

    size_t size() const{return _page_count;}

    auto begin() const { return _pages.begin();}
    auto end() const { return _pages.end();}
private:
    vector<Page<Iterator>> _pages;
    size_t _page_count;

};

template <typename C>
auto Paginate(C& c, size_t page_size) { return Paginator(c.begin(),c.end(), page_size);}