다음은 몇 가지 아이디어/솔루션을 제공해야합니다. 2 개의 렌 디션, 두 번째는 약간 가벼운 무게입니다. 벡터와리스트의 부분 범위를 사용하여 테스트 모두 ... 한편
#include <vector>
template <typename T, typename Container = std::vector<T>, typename Iterator = Container::iterator>
class RingIterator : public std::iterator <std::bidirectional_iterator_tag, T, ptrdiff_t>
{
Container& data;
Iterator cursor;
Iterator begin;
Iterator end;
public:
RingIterator (Container& v) : data(v), cursor(v.begin()), begin(v.begin()), end(v.end()) {}
RingIterator (Container& v, const Iterator& i) : data(v), cursor(i), begin(v.begin()), end(v.end()) {}
RingIterator (Container& v, const Iterator& i, const Iterator& j) : data(v), cursor(i), begin(i), end(j) {}
RingIterator (Container& v, size_t i) : data(v), cursor(v.begin() + i % v.size()), begin(v.begin()), end(v.end()) {}
bool operator == (const RingIterator& x) const
{
return cursor == x.cursor;
}
bool operator != (const RingIterator& x) const
{
return ! (*this == x);
}
reference operator*() const
{
return *cursor;
}
RingIterator& operator++()
{
++cursor;
if (cursor == end)
cursor = begin;
return *this;
}
RingIterator operator++(int)
{
RingIterator ring = *this;
++*this;
return ring;
}
RingIterator& operator--()
{
if (cursor == begin)
cursor = end;
--cursor;
return *this;
}
RingIterator operator--(int)
{
RingIterator ring = *this;
--*this;
return ring;
}
RingIterator insert (const T& x)
{
return RingIterator (data, data.insert (cursor, x));
}
RingIterator erase()
{
return RingIterator (data, data.erase (cursor));
}
};
template <typename T, typename Iterator>
class CyclicIterator : public std::iterator <std::bidirectional_iterator_tag, T, ptrdiff_t>
{
Iterator cursor;
Iterator begin;
Iterator end;
public:
CyclicIterator (const Iterator& i, const Iterator& j) : cursor(i), begin(i), end(j) {}
bool operator == (const CyclicIterator& x) const
{
return cursor == x.cursor;
}
bool operator != (const CyclicIterator& x) const
{
return ! (*this == x);
}
reference operator*() const
{
return *cursor;
}
CyclicIterator& operator++()
{
++cursor;
if (cursor == end)
cursor = begin;
return *this;
}
CyclicIterator operator++(int)
{
CyclicIterator ring = *this;
++*this;
return ring;
}
CyclicIterator& operator--()
{
if (cursor == begin)
cursor = end;
--cursor;
return *this;
}
CyclicIterator operator--(int)
{
CyclicIterator ring = *this;
--*this;
return ring;
}
};
#include <iostream>
#include <iomanip>
#include <list>
enum { CycleSize = 9, ContainerSize };
template <typename cyclicIterator>
void test (cyclicIterator& iterator, size_t mn)
{
int m = mn;
while (m--)
for (int n = mn; n--; ++iterator)
std::cout << std::setw(3) << *iterator << ' ';
--iterator;
m = mn;
while (m--)
for (int n = mn; n--; --iterator)
std::cout << std::setw(3) << *iterator << ' ';
}
template <typename containers>
void load (containers& container)
{
while (container.size() < ContainerSize)
container.push_back (container.size());
}
void main (void)
{
typedef std::vector<int> vContainer;
typedef vContainer::iterator vIterator;
typedef std::list<int> lContainer;
typedef lContainer::iterator lIterator;
vContainer v; load (v);
vIterator vbegin = v.begin() + 1;
RingIterator <int, vContainer, vIterator> vring (v, vbegin, v.end());
CyclicIterator <int, vIterator> vcycle (vbegin, v.end());
lContainer l; load (l);
lIterator lbegin = l.begin(); ++lbegin;
RingIterator <int, lContainer, lIterator> lring (l, lbegin, l.end());
CyclicIterator <int, lIterator> lcycle (lbegin, l.end());
test (vring, CycleSize);
test (vcycle, CycleSize);
test (lring, CycleSize);
test (lcycle, CycleSize);
}
질문 제목에 "표준"이 의미하는 바가 C++ 표준에는 없습니다. –
@Neil : STL이나 Boost 또는 이와 비슷한 라이브러리에 이와 비슷한 라이브러리가 있기를 기대했습니다. +1 코멘트. – Hippicoder
나도 만들었습니다.그것에 대해 흥미로운 점은 ** 연산자 **는 ~ ** (* this! = other) **로 구현되며, 여전히 모든 stl 알고리즘은 모든 범위에서 완벽하게 작동합니다. –