#ifndef CPP_2_COURSE_SOLUTION_H
#define CPP_2_COURSE_SOLUTION_H

#pragma once

#include <vector>

template<class It>
class IteratorRange {
 public:
    IteratorRange(It b, It e) : begin_(b), end_(e),
                                size_(std::distance(b, e)) {}

    It begin() const {
        return begin_;
    }

    It end() const {
        return end_;
    }

    size_t size() const {
        return size_;
    }

 private:
    It begin_, end_;
    size_t size_;
};

template<typename It>
class Slicer {
 public:
    Slicer(It begin, It end, size_t page_size) {
        while (begin != end) {
            auto newEnd =
                page_size <=
                (unsigned int) std::distance(begin, end) ? begin + page_size
                                                         : end;
            IteratorRange<It> temp(begin, newEnd);
            pages_.push_back(temp);
            begin = newEnd;
        }
    }

    auto begin() const {
        return pages_.begin();
    }

    auto end() const {
        return pages_.end();
    }

    size_t size() const {
        return pages_.size();
    }

 private:
    std::vector<IteratorRange<It>> pages_;
};

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

#endif  // CPP_2_COURSE_SOLUTION_H