stl_algo.h

本系统采用VC开发.可实现点云数据的处理,图像缩放,生成曲面.

}

template <class _RandomAccessIter, class _Compare>
inline void nth_element(_RandomAccessIter __first, _RandomAccessIter __nth,
                 _RandomAccessIter __last, _Compare __comp) {
  __nth_element(__first, __nth, __last, __VALUE_TYPE(__first), __comp);
}


// Binary search (lower_bound, upper_bound, equal_range, binary_search).

template <class _ForwardIter, class _T, class _Distance>
_ForwardIter __lower_bound(_ForwardIter __first, _ForwardIter __last,
                           const _T& __val, _Distance*) 
{
  _Distance __len = 0;
  distance(__first, __last, __len);
  _Distance __half;
  _ForwardIter __middle;

  while (__len > 0) {
    __half = __len >> 1;
    __middle = __first;
    advance(__middle, __half);
    if (*__middle < __val) {
      __first = __middle;
      ++__first;
      __len = __len - __half - 1;
    }
    else
      __len = __half;
  }
  return __first;
}

template <class _ForwardIter, class _T>
inline _ForwardIter lower_bound(_ForwardIter __first, _ForwardIter __last,
                                   const _T& __val) {
  return __lower_bound(__first, __last, __val,
                       __DISTANCE_TYPE(__first));
}

template <class _ForwardIter, class _T, class _Compare, class _Distance>
_ForwardIter __lower_bound(_ForwardIter __first, _ForwardIter __last,
                              const _T& __val, _Compare __comp, _Distance*)
{
  _Distance __len = 0;
  distance(__first, __last, __len);
  _Distance __half;
  _ForwardIter __middle;

  while (__len > 0) {
    __half = __len >> 1;
    __middle = __first;
    advance(__middle, __half);
    if (__comp(*__middle, __val)) {
      __first = __middle;
      ++__first;
      __len = __len - __half - 1;
    }
    else
      __len = __half;
  }
  return __first;
}

template <class _ForwardIter, class _T, class _Compare>
inline _ForwardIter lower_bound(_ForwardIter __first, _ForwardIter __last,
                                const _T& __val, _Compare __comp) {
  return __lower_bound(__first, __last, __val, __comp,
                       __DISTANCE_TYPE(__first));
}

template <class _ForwardIter, class _T, class _Distance>
_ForwardIter __upper_bound(_ForwardIter __first, _ForwardIter __last,
                           const _T& __val, _Distance*)
{
  _Distance __len = 0;
  distance(__first, __last, __len);
  _Distance __half;
  _ForwardIter __middle;

  while (__len > 0) {
    __half = __len >> 1;
    __middle = __first;
    advance(__middle, __half);
    if (__val < *__middle)
      __len = __half;
    else {
      __first = __middle;
      ++__first;
      __len = __len - __half - 1;
    }
  }
  return __first;
}

template <class _ForwardIter, class _T>
inline _ForwardIter upper_bound(_ForwardIter __first, _ForwardIter __last,
                                const _T& __val) {
  return __upper_bound(__first, __last, __val,
                       __DISTANCE_TYPE(__first));
}

template <class _ForwardIter, class _T, class _Compare, class _Distance>
_ForwardIter __upper_bound(_ForwardIter __first, _ForwardIter __last,
                           const _T& __val, _Compare __comp, _Distance*)
{
  _Distance __len = 0;
  distance(__first, __last, __len);
  _Distance __half;
  _ForwardIter __middle;

  while (__len > 0) {
    __half = __len >> 1;
    __middle = __first;
    advance(__middle, __half);
    if (__comp(__val, *__middle))
      __len = __half;
    else {
      __first = __middle;
      ++__first;
      __len = __len - __half - 1;
    }
  }
  return __first;
}

template <class _ForwardIter, class _T, class _Compare>
inline _ForwardIter upper_bound(_ForwardIter __first, _ForwardIter __last,
                                const _T& __val, _Compare __comp) {
  return __upper_bound(__first, __last, __val, __comp,
                       __DISTANCE_TYPE(__first));
}

template <class _ForwardIter, class _T, class _Distance>
pair<_ForwardIter, _ForwardIter>
__equal_range(_ForwardIter __first, _ForwardIter __last, const _T& __val,
              _Distance*)
{
  _Distance __len = 0;
  distance(__first, __last, __len);
  _Distance __half;
  _ForwardIter __middle, __left, __right;

  while (__len > 0) {
    __half = __len >> 1;
    __middle = __first;
    advance(__middle, __half);
    if (*__middle < __val) {
      __first = __middle;
      ++__first;
      __len = __len - __half - 1;
    }
    else if (__val < *__middle)
      __len = __half;
    else {
      __left = lower_bound(__first, __middle, __val);
      advance(__first, __len);
      __right = upper_bound(++__middle, __first, __val);
      return pair<_ForwardIter, _ForwardIter>(__left, __right);
    }
  }
  return pair<_ForwardIter, _ForwardIter>(__first, __first);
}

template <class _ForwardIter, class _T>
inline pair<_ForwardIter, _ForwardIter>
equal_range(_ForwardIter __first, _ForwardIter __last, const _T& __val) {
  return __equal_range(__first, __last, __val,
                       __DISTANCE_TYPE(__first));
}

template <class _ForwardIter, class _T, class _Compare, class _Distance>
pair<_ForwardIter, _ForwardIter>
__equal_range(_ForwardIter __first, _ForwardIter __last, const _T& __val,
              _Compare __comp, _Distance*)
{
  _Distance __len = 0;
  distance(__first, __last, __len);
  _Distance __half;
  _ForwardIter __middle, __left, __right;

  while (__len > 0) {
    __half = __len >> 1;
    __middle = __first;
    advance(__middle, __half);
    if (__comp(*__middle, __val)) {
      __first = __middle;
      ++__first;
      __len = __len - __half - 1;
    }
    else if (__comp(__val, *__middle))
      __len = __half;
    else {
      __left = lower_bound(__first, __middle, __val, __comp);
      advance(__first, __len);
      __right = upper_bound(++__middle, __first, __val, __comp);
      return pair<_ForwardIter, _ForwardIter>(__left, __right);
    }
  }
  return pair<_ForwardIter, _ForwardIter>(__first, __first);
}           

template <class _ForwardIter, class _T, class _Compare>
inline pair<_ForwardIter, _ForwardIter>
equal_range(_ForwardIter __first, _ForwardIter __last, const _T& __val,
            _Compare __comp) {
  return __equal_range(__first, __last, __val, __comp,
                       __DISTANCE_TYPE(__first));
} 

template <class _ForwardIter, class _T>
bool binary_search(_ForwardIter __first, _ForwardIter __last,
                   const _T& __val) {
  _ForwardIter __i = lower_bound(__first, __last, __val);
  return __i != __last && !(__val < *__i);
}

template <class _ForwardIter, class _T, class _Compare>
bool binary_search(_ForwardIter __first, _ForwardIter __last, const _T& __val,
                   _Compare __comp) {
  _ForwardIter __i = lower_bound(__first, __last, __val, __comp);
  return __i != __last && !__comp(__val, *__i);
}

// merge, with and without an explicitly supplied comparison function.

template <class _InputIter1, class _InputIter2, class _OutputIter>
_OutputIter merge(_InputIter1 __first1, _InputIter1 __last1,
                  _InputIter2 __first2, _InputIter2 __last2,
                  _OutputIter __result) {
  while (__first1 != __last1 && __first2 != __last2) {
    if (*__first2 < *__first1) {
      *__result = *__first2;
      ++__first2;
    }
    else {
      *__result = *__first1;
      ++__first1;
    }
    ++__result;
  }
  return copy(__first2, __last2, copy(__first1, __last1, __result));
}

template <class _InputIter1, class _InputIter2, class _OutputIter,
          class _Compare>
_OutputIter merge(_InputIter1 __first1, _InputIter1 __last1,
                  _InputIter2 __first2, _InputIter2 __last2,
                  _OutputIter __result, _Compare __comp) {
  while (__first1 != __last1 && __first2 != __last2) {
    if (__comp(*__first2, *__first1)) {
      *__result = *__first2;
      ++__first2;
    }
    else {
      *__result = *__first1;
      ++__first1;
    }
    ++__result;
  }
  return copy(__first2, __last2, copy(__first1, __last1, __result));
}

// inplace_merge and its auxiliary functions. 

template <class _BidirectionalIter, class _Distance>
void __merge_without_buffer(_BidirectionalIter __first,
                            _BidirectionalIter __middle,
                            _BidirectionalIter __last,
                            _Distance __len1, _Distance __len2) {
  if (__len1 == 0 || __len2 == 0)
    return;
  if (__len1 + __len2 == 2) {
    if (*__middle < *__first)
      iter_swap(__first, __middle);
    return;
  }
  _BidirectionalIter __first_cut = __first;
  _BidirectionalIter __second_cut = __middle;
  _Distance __len11 = 0;
  _Distance __len22 = 0;
  if (__len1 > __len2) {
    __len11 = __len1 / 2;
    advance(__first_cut, __len11);
    __second_cut = lower_bound(__middle, __last, *__first_cut);
    distance(__middle, __second_cut, __len22);
  }
  else {
    __len22 = __len2 / 2;
    advance(__second_cut, __len22);
    __first_cut = upper_bound(__first, __middle, *__second_cut);
    distance(__first, __first_cut, __len11);
  }
  _BidirectionalIter __new_middle
    = rotate(__first_cut, __middle, __second_cut);
  __merge_without_buffer(__first, __first_cut, __new_middle,
                         __len11, __len22);
  __merge_without_buffer(__new_middle, __second_cut, __last, __len1 - __len11,
                         __len2 - __len22);
}

template <class _BidirectionalIter, class _Distance, class _Compare>
void __merge_without_buffer(_BidirectionalIter __first,
                            _BidirectionalIter __middle,
                            _BidirectionalIter __last,
                            _Distance __len1, _Distance __len2,
                            _Compare __comp) {
  if (__len1 == 0 || __len2 == 0)
    return;
  if (__len1 + __len2 == 2) {
    if (__comp(*__middle, *__first))
      iter_swap(__first, __middle);
    return;
  }
  _BidirectionalIter __first_cut = __first;
  _BidirectionalIter __second_cut = __middle;
  _Distance __len11 = 0;
  _Distance __len22 = 0;
  if (__len1 > __len2) {
    __len11 = __len1 / 2;
    advance(__first_cut, __len11);
    __second_cut = lower_bound(__middle, __last, *__first_cut, __comp);
    distance(__middle, __second_cut, __len22);
  }
  else {
    __len22 = __len2 / 2;
    advance(__second_cut, __len22);
    __first_cut = upper_bound(__first, __middle, *__second_cut, __comp);
    distance(__first, __first_cut, __len11);
  }
  _BidirectionalIter __new_middle
    = rotate(__first_cut, __middle, __second_cut);
  __merge_without_buffer(__first, __first_cut, __new_middle, __len11, __len22,
                         __comp);
  __merge_without_buffer(__new_middle, __second_cut, __last, __len1 - __len11,
                         __len2 - __len22, __comp);
}

template <class _BidirectionalIter1, class _BidirectionalIter2,
          class _Distance>
_BidirectionalIter1 __rotate_adaptive(_BidirectionalIter1 __first,
                                      _BidirectionalIter1 __middle,
                                      _BidirectionalIter1 __last,
                                      _Distance __len1, _Distance __len2,
                                      _BidirectionalIter2 __buffer,
                                      _Distance __buffer_size) {
  _BidirectionalIter2 __buffer_end;
  if (__len1 > __len2 && __len2 <= __buffer_size) {
    __buffer_end = copy(__middle, __last, __buffer);
    copy_backward(__first, __middle, __last);
    return copy(__buffer, __buffer_end, __first);
  }
  else if (__len1 <= __buffer_size) {
    __buffer_end = copy(__first, __middle, __buffer);
    copy(__middle, __last, __first);
    return copy_backward(__buffer, __buffer_end, __last);
  }
  else
    return rotate(__first, __middle, __last);
}

template <class _BidirectionalIter1, class _BidirectionalIter2,
          class _BidirectionalIter3>
_BidirectionalIter3 __merge_backward(_BidirectionalIter1 __first1,
                                     _BidirectionalIter1 __last1,
                                     _BidirectionalIter2 __first2,
                                     _BidirectionalIter2 __last2,
                                     _BidirectionalIter3 __result) {
  if (__first1 == __last1)
    return copy_backward(__first2, __last2, __result);
  if (__first2 == __last2)
    return copy_backward(__first1, __last1, __result);
  --__last1;
  --__last2;
  while (true) {
    if (*__last2 < *__last1) {
      *--__result = *__last1;
      if (__first1 == __last1)
        return copy_backward(__first2, ++__last2, __result);
      --__last1;
    }
    else {
      *--__result = *__last2;
      if (__first2 == __last2)
        return copy_backward(__first1, ++__last1, __result);
      --__last2;
    }
  }
}

template <class _BidirectionalIter1, class _BidirectionalIter2,
          class _BidirectionalIter3, class _Compare>
_BidirectionalIter3 __merge_backward(_BidirectionalIter1 __first1,
                                     _BidirectionalIter1 __last1,
                                     _BidirectionalIter2 __first2,
                                     _BidirectionalIter2 __last2,