ResizeArray.h

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/*
   ResizeArray template
   Uses simple contingous array allocation in a hidden manner
   so that array object can have items added without limit
   Suffers from memory fragmentation during resizing
   Fast access, safe and efficient passing of encapsulated array thru
   function arguments.
*/

#ifndef RESIZEARRAY_H
#define RESIZEARRAY_H

#include "ResizeArrayRaw.h"

// Need this juju to use templated friend below
template <class Type> class ResizeArrayIter;
template <class Type> class ResizeArrayRaw;

template <class Elem> class ResizeArray {
  friend class ResizeArrayIter<Elem>;

  protected:
    ResizeArrayRaw<Elem> *rep;

  public:
    // STL style iterators
    typedef Elem* iterator;
    iterator begin(void) { return rep->array; }
    iterator end(void) { return rep->array + rep->arraySize; }
    typedef const Elem* const_iterator;
    const_iterator const_begin(void) const { return rep->array; }
    const_iterator const_end(void) const { return rep->array + rep->arraySize; }

    // Various Constructors
    ResizeArray(void) {
      rep = new ResizeArrayRaw<Elem>();
      rep->resize(0);
      rep->refCount = 1;
    }

    // Constructor make ResizeArray of predefined size
    ResizeArray(int s) {
      rep = new ResizeArrayRaw<Elem>();
      rep->resize(s);
      rep->refCount = 1;
    }

    // Contructor makes ResizeArray which points to same ResizeArrayRaw
    ResizeArray(ResizeArray<Elem> &ra) {
      rep = ra.rep;
      rep->refCount++;
    }

    // Constructor makes a copy of ResizeArrayRaw
    ResizeArray(const ResizeArray<Elem>* ra) {
      rep = new ResizeArrayRaw<Elem>(*(ra->rep));
      rep->refCount = 1;
    }

    // Constructor to take-in pre-existing array
    ResizeArray(Elem * * array, int arraySize, int allocSize=0) {
      rep = new ResizeArrayRaw<Elem>(array, arraySize, allocSize);
      rep->refCount = 1;
    }

    virtual ~ResizeArray(void) {
      if (!--rep->refCount) delete rep;
    }

    // We copy reference to ResizeArrayRaw
    ResizeArray<Elem> & operator= (ResizeArray<Elem> &ra) {
      if (rep != NULL && !(--rep->refCount) )
        delete rep;
      rep = ra.rep;
      rep->refCount++;
      return (*this);
    }

    // Set the initial allocation size to s with growth factor as growthFactor
    void setParams(int s, float growthFactor) {      
      rep->setResizeParams(s, growthFactor);
    }


    // If array is expanded - new elements are default constructed
    // if array is reduced, removed elements have ~Elem() run
    void resize(int i) { rep->resize(i); }

    // Set all elements to a given value (like 0).
    void setall(const Elem &elem) {
      iterator i = begin();
      iterator e = end();
      for ( ; i != e; ++i ) *i = elem;
    }
  
    // Add element to end of array
    int add (const Elem &elem) {
      int end=rep->size();
      rep->ins(elem, end);
      return(end);
    }
  
    // delete num elements from current index
    int del(int index, int num=1) {
      return(rep->del(index,num));
    }

    // insert element at index
    int insert (const Elem& elem, int index) {
      rep->ins(elem,index);
      return (index);
    }

    // array member access (can be lvalue) that grows array.
    inline Elem & item(int i) {
      i = ( i < 0 ? 0 : i );
      if ((i+1) > size())
          resize(i+1);
      return rep->array[i];
    }

    // array member access (can be lvalue) no checks.
    inline Elem & operator[](int index) { return rep->array[index]; }
    inline const Elem & operator[](int index) const { return rep->array[index]; }

    // returns size of ResizeArray
    inline int size(void) const { return rep->size(); }

    // reduce storage size
    void reduce(void) { rep->reduce(); }

    inline int find(const Elem &e) const { return rep->find(e); }

        // Difference with resize(0): 
        // This function will free the space occupied by rep,
        // while resize(0) will not.    
        void clear() { 
                if (!--rep->refCount){
                        delete rep;
                        rep = new ResizeArrayRaw<Elem>();
                        rep->resize(0);
                        rep->refCount = 1; 
                }
        }
};

#endif

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