dynarray.cpp

来自「A*算法 A*算法 A*算法 A*算法A*算法A*算法」· C++ 代码 · 共 535 行 · 第 1/3 页

/* grow the array */                                                        \
void name::Grow(size_t nIncrement)                                          \
{                                                                           \
  /* only do it if no more place */                                         \
  if( (m_nCount == m_nSize) || ((m_nSize - m_nCount) < nIncrement) ) {      \
    if( m_nSize == 0 ) {                                                    \
      /* was empty, determine initial size */                               \
      size_t size = WX_ARRAY_DEFAULT_INITIAL_SIZE;                          \
      if (size < nIncrement) size = nIncrement;                             \
      /* allocate some memory */                                            \
      m_pItems = new T[size];                                               \
      /* only grow if allocation succeeded */                               \
      if ( m_pItems ) {                                                     \
          m_nSize = size;                                                   \
      }                                                                     \
    }                                                                       \
    else                                                                    \
    {                                                                       \
      /* add at least 50% but not too much */                               \
      size_t ndefIncrement = m_nSize < WX_ARRAY_DEFAULT_INITIAL_SIZE        \
                            ? WX_ARRAY_DEFAULT_INITIAL_SIZE : m_nSize >> 1; \
      if ( ndefIncrement > ARRAY_MAXSIZE_INCREMENT )                        \
        ndefIncrement = ARRAY_MAXSIZE_INCREMENT;                            \
      if ( nIncrement < ndefIncrement )                                     \
        nIncrement = ndefIncrement;                                         \
      Realloc(m_nSize + nIncrement);                                        \
    }                                                                       \
  }                                                                         \
}                                                                           \
                                                                            \
/* make sure that the array has at least count elements */                  \
void name::SetCount(size_t count, T defval)                                 \
{                                                                           \
    if ( m_nSize < count )                                                  \
    {                                                                       \
        /* need to realloc memory: don't overallocate it here as if */      \
        /* SetCount() is called, it probably means that the caller  */      \
        /* knows in advance how many elements there will be in the  */      \
        /* array and so it won't be necessary to realloc it later   */      \
        if ( !Realloc(count) )                                              \
        {                                                                   \
            /* out of memory -- what can we do? */                          \
            return;                                                         \
        }                                                                   \
    }                                                                       \
                                                                            \
    /* add new elements if we extend the array */                           \
    while ( m_nCount < count )                                              \
    {                                                                       \
        m_pItems[m_nCount++] = defval;                                      \
    }                                                                       \
}                                                                           \
                                                                            \
/* dtor */                                                                  \
name::~name()                                                               \
{                                                                           \
  wxDELETEA(m_pItems);                                                      \
}                                                                           \
                                                                            \
/* clears the list */                                                       \
void name::Clear()                                                          \
{                                                                           \
  m_nSize  =                                                                \
  m_nCount = 0;                                                             \
                                                                            \
  wxDELETEA(m_pItems);                                                      \
}                                                                           \
                                                                            \
/* pre-allocates memory (frees the previous data!) */                       \
void name::Alloc(size_t nSize)                                              \
{                                                                           \
  /* only if old buffer was not big enough */                               \
  if ( nSize > m_nSize ) {                                                  \
    wxDELETEA(m_pItems);                                                    \
    m_nSize  = 0;                                                           \
    m_pItems = new T[nSize];                                                \
    /* only alloc if allocation succeeded */                                \
    if ( m_pItems ) {                                                       \
        m_nSize  = nSize;                                                   \
    }                                                                       \
  }                                                                         \
                                                                            \
  m_nCount = 0;                                                             \
}                                                                           \
                                                                            \
/* minimizes the memory usage by freeing unused memory */                   \
void name::Shrink()                                                         \
{                                                                           \
  /* only do it if we have some memory to free */                           \
  if( m_nCount < m_nSize ) {                                                \
    /* allocates exactly as much memory as we need */                       \
    T *pNew = new T[m_nCount];                                              \
    /* only shrink if allocation succeeded */                               \
    if ( pNew ) {                                                           \
        /* copy data to new location */                                     \
        memcpy(pNew, m_pItems, m_nCount*sizeof(T));                         \
        delete [] m_pItems;                                                 \
        m_pItems = pNew;                                                    \
                                                                            \
        /* update the size of the new block */                              \
        m_nSize = m_nCount;                                                 \
    }                                                                       \
    /* else: don't do anything, better keep old memory block! */            \
  }                                                                         \
}                                                                           \
                                                                            \
/* add item at the end */                                                   \
void name::Add(T lItem, size_t nInsert)                                     \
{                                                                           \
  if (nInsert == 0)                                                         \
      return;                                                               \
  Grow(nInsert);                                                            \
  for (size_t i = 0; i < nInsert; i++)                                      \
      m_pItems[m_nCount++] = lItem;                                         \
}                                                                           \
                                                                            \
/* add item at the given position */                                        \
void name::Insert(T lItem, size_t nIndex, size_t nInsert)                   \
{                                                                           \
  wxCHECK_RET( nIndex <= m_nCount, wxT("bad index in wxArray::Insert") );   \
  wxCHECK_RET( m_nCount <= m_nCount + nInsert,                              \
               wxT("array size overflow in wxArray::Insert") );             \
                                                                            \
  if (nInsert == 0)                                                         \
      return;                                                               \
  Grow(nInsert);                                                            \
                                                                            \
  memmove(&m_pItems[nIndex + nInsert], &m_pItems[nIndex],                   \
          (m_nCount - nIndex)*sizeof(T));                                   \
  for (size_t i = 0; i < nInsert; i++)                                      \
      m_pItems[nIndex + i] = lItem;                                         \
  m_nCount += nInsert;                                                      \
}                                                                           \
                                                                            \
/* search for a place to insert item into sorted array (binary search) */   \
size_t name::IndexForInsert(T lItem, CMPFUNC fnCompare) const               \
{                                                                           \
  size_t i,                                                                 \
       lo = 0,                                                              \
       hi = m_nCount;                                                       \
  int res;                                                                  \
                                                                            \
  while ( lo < hi ) {                                                       \
    i = (lo + hi)/2;                                                        \
                                                                            \
    res = (*fnCompare)((const void *)(wxUIntPtr)lItem,                      \
                       (const void *)(wxUIntPtr)(m_pItems[i]));             \
    if ( res < 0 )                                                          \
      hi = i;                                                               \
    else if ( res > 0 )                                                     \
      lo = i + 1;                                                           \
    else {                                                                  \
      lo = i;                                                               \
      break;                                                                \
    }                                                                       \
  }                                                                         \
                                                                            \
  return lo;                                                                \
}                                                                           \
                                                                            \
/* search for an item in a sorted array (binary search) */                  \
int name::Index(T lItem, CMPFUNC fnCompare) const                           \
{                                                                           \
    size_t n = IndexForInsert(lItem, fnCompare);                            \
                                                                            \
    return (n >= m_nCount ||                                                \
           (*fnCompare)((const void *)(wxUIntPtr)lItem,                     \
                        ((const void *)(wxUIntPtr)m_pItems[n])))            \
                        ? wxNOT_FOUND                                       \
                        : (int)n;                                           \
}                                                                           \
                                                                            \
/* removes item from array (by index) */                                    \
void name::RemoveAt(size_t nIndex, size_t nRemove)                          \
{                                                                           \
  wxCHECK_RET( nIndex < m_nCount, wxT("bad index in wxArray::RemoveAt") );  \
  wxCHECK_RET( nIndex + nRemove <= m_nCount,                                \
               wxT("removing too many elements in wxArray::RemoveAt") );    \
                                                                            \