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Dynamic ADT Implementation help. I need help fixing my BagTester.cpp/main progra

ID: 3587320 • Letter: D

Question

Dynamic ADT Implementation help. I need help fixing my BagTester.cpp/main program.

Methods must compose a new Bag object by accessing the elements of the underlying linked list of the Bag objects. You may not convert the Bags to vectors. The main method must also be updated to thoroughly test the newly added methods.

1. bagUnion(): The union of two bags is a new bag containing the combined contents of the original two bags. Design and specify a method union for the LinkedBag that returns as a new bag the union of the bag receiving the call to the method and the bag that is the method's parameter. Note that the union of two bags might contain duplicate items. For example, if object x occurs five times in one bag and twice in another, the union of these bags contains x seven times. The union does not affect the contents of the original bags.

2. bagIntersection(): The intersection of two bags is a new bag containing the entries that occur in both of the original bags. Design and specify a method intersection for the LinkedBag that returns as a new bag the intersection of the bag receiving the call to the method and the bag that is the method's parameter. Note that the intersection of two bags might contain duplicate items. For example, if object x occurs five times in one bag and twice in another, the intersection of these bags contains x two times. The intersection does not affect the contents of the original bags.

3. bagDifference(): The difference of two bags is a new bag containing the entries (from both bag) that would be unique in one bag (not duplicated in its own bag, also not another bag). Design and specify a method difference for the LinkedBag that returns as a new bag the difference from the two bags (the bag receiving the call to the method and the bag that is the method's parameter). Note that the difference of two bags does not contain duplicate items. For example, if object x occurs more than one time in one bag and no in another, the difference of these bags contains x only one time.

For testing the new methods, please output original contents in two bags and clear message for each testing, for example:

Bag 1 contains: 1 2 3 4 5 1

Bag 2 contains: 4 5 6 7 8 8

Test union method … 1 2 3 4 5 1 4 5 6 7 8 8

Test intersection method … 4 5

Test difference method … 1 2 3 6 7 8

LinkedBag.cpp

#include "LinkedBag.h"

#include "Node.h"

#include <cstddef>

template<class ItemType>

LinkedBag<ItemType>::LinkedBag() : headPtr(nullptr), itemCount(0)

{

} // end default constructor

template<class ItemType>

LinkedBag<ItemType>::LinkedBag(const LinkedBag<ItemType>& aBag)

{

itemCount = aBag.itemCount;

Node<ItemType>* origChainPtr = aBag.headPtr; // Points to nodes in original chain

if (origChainPtr == nullptr)

headPtr = nullptr; // Original bag is empty

else

{

// Copy first node

headPtr = new Node<ItemType>();

headPtr->setItem(origChainPtr->getItem());

  

// Copy remaining nodes

Node<ItemType>* newChainPtr = headPtr; // Points to last node in new chain

origChainPtr = origChainPtr->getNext(); // Advance original-chain pointer

  

while (origChainPtr != nullptr)

{

// Get next item from original chain

ItemType nextItem = origChainPtr->getItem();

  

// Create a new node containing the next item

Node<ItemType>* newNodePtr = new Node<ItemType>(nextItem);

// Link new node to end of new chain

newChainPtr->setNext(newNodePtr);

// Advance pointer to new last node

newChainPtr = newChainPtr->getNext();

  

// Advance original-chain pointer

origChainPtr = origChainPtr->getNext();

} // end while

  

newChainPtr->setNext(nullptr); // Flag end of chain

} // end if

} // end copy constructor

template<class ItemType>

LinkedBag<ItemType>::~LinkedBag()

{

clear();

} // end destructor

template<class ItemType>

bool LinkedBag<ItemType>::isEmpty() const

{

return itemCount == 0;

} // end isEmpty

template<class ItemType>

int LinkedBag<ItemType>::getCurrentSize() const

{

return itemCount;

} // end getCurrentSize

template<class ItemType>

bool LinkedBag<ItemType>::add(const ItemType& newEntry)

{

// Add to beginning of chain: new node references rest of chain;

// (headPtr is null if chain is empty)   

Node<ItemType>* nextNodePtr = new Node<ItemType>();

nextNodePtr->setItem(newEntry);

nextNodePtr->setNext(headPtr); // New node points to chain

// Node<ItemType>* nextNodePtr = new Node<ItemType>(newEntry, headPtr); // alternate code

headPtr = nextNodePtr; // New node is now first node

itemCount++;

return true;

} // end add

template<class ItemType>

vector<ItemType> LinkedBag<ItemType>::toVector() const

{

vector<ItemType> bagContents;

Node<ItemType>* curPtr = headPtr;

int counter = 0;

while ((curPtr != nullptr) && (counter < itemCount))

{

bagContents.push_back(curPtr->getItem());

curPtr = curPtr->getNext();

counter++;

} // end while

return bagContents;

} // end toVector

template<class ItemType>

bool LinkedBag<ItemType>::remove(const ItemType& anEntry)

{

Node<ItemType>* entryNodePtr = getPointerTo(anEntry);

bool canRemoveItem = !isEmpty() && (entryNodePtr != nullptr);

if (canRemoveItem)

{

// Copy data from first node to located node

entryNodePtr->setItem(headPtr->getItem());

  

// Delete first node

Node<ItemType>* nodeToDeletePtr = headPtr;

headPtr = headPtr->getNext();

  

// Return node to the system

nodeToDeletePtr->setNext(nullptr);

delete nodeToDeletePtr;

nodeToDeletePtr = nullptr;

  

itemCount--;

} // end if

return canRemoveItem;

} // end remove

template<class ItemType>

void LinkedBag<ItemType>::clear()

{

Node<ItemType>* nodeToDeletePtr = headPtr;

while (headPtr != nullptr)

{

headPtr = headPtr->getNext();

// Return node to the system

nodeToDeletePtr->setNext(nullptr);

delete nodeToDeletePtr;

  

nodeToDeletePtr = headPtr;

} // end while

// headPtr is nullptr; nodeToDeletePtr is nullptr

itemCount = 0;

} // end clear

template<class ItemType>

int LinkedBag<ItemType>::getFrequencyOf(const ItemType& anEntry) const

{

int frequency = 0;

int counter = 0;

Node<ItemType>* curPtr = headPtr;

while ((curPtr != nullptr) && (counter < itemCount))

{

if (anEntry == curPtr->getItem())

{

frequency++;

} // end if

  

counter++;

curPtr = curPtr->getNext();

} // end while

return frequency;

} // end getFrequencyOf

template<class ItemType>

bool LinkedBag<ItemType>::contains(const ItemType& anEntry) const

{

return (getPointerTo(anEntry) != nullptr);

} // end contains

/* ALTERNATE 1

template<class ItemType>

bool LinkedBag<ItemType>::contains(const ItemType& anEntry) const

{

return getFrequencyOf(anEntry) > 0;

}

*/

/* ALTERNATE 2

template<class ItemType>

bool LinkedBag<ItemType>::contains(const ItemType& anEntry) const

{

bool found = false;

Node<ItemType>* curPtr = headPtr;

int i = 0;

while (!found && (curPtr != nullptr) && (i < itemCount))

{

if (anEntry == curPtr-<getItem())

{

found = true;

}

else

{

i++;

curPtr = curPtr->getNext();

} // end if

} // end while

return found;

} // end contains

*/

// private

// Returns either a pointer to the node containing a given entry

// or the null pointer if the entry is not in the bag.

template<class ItemType>

Node<ItemType>* LinkedBag<ItemType>::getPointerTo(const ItemType& anEntry) const

{

bool found = false;

Node<ItemType>* curPtr = headPtr;

while (!found && (curPtr != nullptr))

{

if (anEntry == curPtr->getItem())

found = true;

else

curPtr = curPtr->getNext();

} // end while

return curPtr;

} // end getPointerTo

//My methods

template<class ItemType>

LinkedBag<ItemType> LinkedBag<ItemType>::bagUnion(const LinkedBag &otherBag) const

{

LinkedBag uni(*this);//create a bag with this bag's contents

//traverse the other bag and each of the nodes

Node<ItemType>* curPtr = otherBag.headPtr;

while(curPtr != nullptr)

{

uni.add(curPtr->getItem());

curPtr = curPtr->getNext();

}

return uni;

}

template<class ItemType>

LinkedBag<ItemType> LinkedBag<ItemType>::bagIntersection(const LinkedBag &otherBag) const

{

int this_count, other_count;

int how_many;

Node<ItemType>* curPtr = otherBag.headPtr;

LinkedBag inter;

while(curPtr != nullptr)

{

if(!inter.contains(curPtr->getItem())) //only if we have not already process the current item

{

//get the counts of the current item in both the bags, and add occurences as many as the lowest of the 2 counts

this_count = getFrequencyOf(curPtr->getItem());

other_count = otherBag.getFrequencyOf(curPtr->getItem());

if(this_count < other_count)

how_many = this_count;

else

how_many = other_count;

for(int i = 1; i <= how_many; i++)

inter.add(curPtr->getItem());

}

}

}

template<class ItemType>

LinkedBag<ItemType> LinkedBag<ItemType>::bagDifference(const LinkedBag &otherBag) const

{

int this_count, other_count;

int how_many;

Node<ItemType>* curPtr = otherBag.headPtr;

LinkedBag diff;

while(curPtr != nullptr)

{

if(!diff.contains(curPtr->getItem())) //only if we have not already process the current item

{

//get the counts of the current item in both the bags, and add occurences as many as the lowest of the 2 counts

this_count = getFrequencyOf(curPtr->getItem());

other_count = otherBag.getFrequencyOf(curPtr->getItem());

if(this_count > other_count) //we need to add only if we get 1 or more difference between the counts

{

how_many = this_count - other_count;

for(int i = 1; i <= how_many; i++)

diff.add(curPtr->getItem());

}

}

}

}

BagTester.cpp/main program

#include <iostream>

#include <string>

#include "LinkedBag.h"

using namespace std;

void displayBag(LinkedBag<int>& bag);

void bagTester(LinkedBag<int>& bag);

void displayBag(LinkedBag<string>& bag)

{

cout << "The bag contains " << bag.getCurrentSize()

<< " items:" << endl;

vector<string> bagItems = bag.toVector();

int numberOfEntries = (int) bagItems.size();

for (int i = 0; i < numberOfEntries; i++)

{

cout << bagItems[i] << " ";

} // end for

cout << endl << endl;

} // end displayBag

void copyConstructorTester()

{

LinkedBag<string> bag;

string items[] = {"zero", "one", "two", "three", "four", "five"};

for (int i = 0; i < 6; i++)

{

cout << "Adding " << items[i] << endl;

bool success = bag.add(items[i]);

if (!success)

cout << "Failed to add " << items[i] << " to the bag." << endl;

}

displayBag(bag);

LinkedBag<string> copyOfBag(bag);

cout << "Copy of bag: ";

displayBag(copyOfBag);

cout << "The copied bag: ";

displayBag(bag);

} // end copyConstructorTester

void bagTester(LinkedBag<int>& bag)

{

/*

LinkedBag<string> bag;

cout << "Testing the Link-Based Bag:" << endl;

cout << "isEmpty: returns " << bag.isEmpty()

<< "; should be 1 (true)" << endl;

displayBag(bag);

string items[] = {"one", "two", "three", "four", "five", "one"};

cout << "Add 6 items to the bag: " << endl;

for (int i = 0; i < 6; i++)

{

bag.add(items[i]);

} // end for

displayBag(bag);

displayBag(bag);

*/

LinkedBag<int> sack; //a sack is a bag too, right?

LinkedBag<int> newBag;

cout << " Populating first bag... ";

int a[] = {1,1,2,4,5,3,7,8,9,1,1,6};

for(int i=0;i<12;i++)

bag.add(a[i]);

cout << "done." << endl;

displayBag(bag);

  

cout << " Creating second bag and populating... ";

int b[] = {20, 30, 40, 50, 1, 18, 1, 15, 9, 8, 7, 2};

for(int i=0;i<12;i++)

sack.add(b[i]);

cout << "done." << endl;

displayBag(sack);

cout << " Testing the union of the two bags: " << endl;

newBag = bag.bagUnion(sack);

displayBag(newBag);

cout << "Done. Testing the difference of the first bag from the second: " << endl;

newBag = bag.bagDifference(sack);

displayBag(newBag);

cout << "Done. Testing the difference of the second bag from the first: " << endl;

newBag = sack.bagDifference(bag);

displayBag(newBag);

  

cout << "Done. Testing the intersection of the two bags: " << endl;

newBag = bag.bagIntersection(sack);

displayBag(newBag);

} // end bagTester

int main()

{

LinkedBag<int> bag;

copyConstructorTester();

bagTester(bag);

return 0;

} // end main

Explanation / Answer

Solution:

LinkedBag.h
#ifndef _LINKED_BAG
#define _LINKED_BAG

#include "BagInterface.h"
#include "Node.h"

template<class ItemType>
class LinkedBag : public BagInterface<ItemType>
{
private:
   Node<ItemType>* headPtr; // Pointer to first node
   int itemCount;           // Current count of bag items

   // Returns either a pointer to the node containing a given entry
   // or the null pointer if the entry is not in the bag.
   Node<ItemType>* getPointerTo(const ItemType& target) const;

public:
   LinkedBag();
   LinkedBag(const LinkedBag<ItemType>& aBag); // Copy constructor
   virtual ~LinkedBag();                       // Destructor should be virtual
   int getCurrentSize() const;
   bool isEmpty() const;
   bool add(const ItemType& newEntry);
   bool remove(const ItemType& anEntry);
   void clear();
   bool contains(const ItemType& anEntry) const;
   int getFrequencyOf(const ItemType& anEntry) const;
   vector<ItemType> toVector() const;
   LinkedBag<ItemType>bagUnion(const LinkedBag& input) const; // Lab 4-1
   LinkedBag<ItemType> intersect(const LinkedBag& input) const; //Lab 4-2
   LinkedBag<ItemType> trueIntersect(const LinkedBag& input) const;
   LinkedBag<ItemType> difference(const LinkedBag& input) const; // Lab 4-3
   LinkedBag<ItemType> trueDifference(const LinkedBag& input) const;
}; // end LinkedBag

#include "LinkedBag.cpp"
#endif

BagInterface.h
#ifndef _BAG_INTERFACE
#define _BAG_INTERFACE

#include <vector>
using namespace std;

template<class ItemType>
class BagInterface
{
public:
   /** Gets the current number of entries in this bag.
    @return The integer number of entries currently in the bag. */
   virtual int getCurrentSize() const = 0;

   /** Sees whether this bag is empty.
    @return True if the bag is empty, or false if not. */
   virtual bool isEmpty() const = 0;

   /** Adds a new entry to this bag.
    @post If successful, newEntry is stored in the bag and
       the count of items in the bag has increased by 1.
    @param newEntry The object to be added as a new entry.
    @return True if addition was successful, or false if not. */
   virtual bool add(const ItemType& newEntry) = 0;

   /** Removes one occurrence of a given entry from this bag,
       if possible.
    @post If successful, anEntry has been removed from the bag
       and the count of items in the bag has decreased by 1.
    @param anEntry The entry to be removed.
    @return True if removal was successful, or false if not. */
   virtual bool remove(const ItemType& anEntry) = 0;

   /** Removes all entries from this bag.
    @post Bag contains no items, and the count of items is 0. */
   virtual void clear() = 0;

   /** Counts the number of times a given entry appears in bag.
    @param anEntry The entry to be counted.
    @return The number of times anEntry appears in the bag. */
   virtual int getFrequencyOf(const ItemType& anEntry) const = 0;

   /** Tests whether this bag contains a given entry.
    @param anEntry The entry to locate.
    @return True if bag contains anEntry, or false otherwise. */
   virtual bool contains(const ItemType& anEntry) const = 0;

   /** Empties and then f ills a given vector with all entries that
       are in this bag.
    @return A vector containing all the entries in the bag. */
   virtual vector<ItemType> toVector() const = 0;
}; // end BagInterface
#endif

BagTester.cpp
#include <iostream>
#include <string>
#include "LinkedBag.h"

using namespace std;

void displayBag(LinkedBag<string>& bag)
{
   cout << "The bag contains " << bag.getCurrentSize()
        << " items:" << endl;
   vector<string> bagItems = bag.toVector();

   int numberOfEntries = (int) bagItems.size();
   for (int i = 0; i < numberOfEntries; i++)
   {
      cout << bagItems[i] << " ";
   } // end for
   cout << endl << endl;
} // end displayBag

void copyConstructorTester()
{
   LinkedBag<string> bag;
   string items[] = {"zero", "one", "two", "three", "four", "five"};
   for (int i = 0; i < 6; i++)
   {
       cout << "Adding " << items[i] << endl;
      bool success = bag.add(items[i]);
      if (!success)
         cout << "Failed to add " << items[i] << " to the bag." << endl;
   }
   displayBag(bag);

   LinkedBag<string> copyOfBag(bag);
   cout << "Copy of bag: ";
   displayBag(copyOfBag);

   cout << "The copied bag: ";
   displayBag(bag);
} // end copyConstructorTester

void bagTester()
{
   LinkedBag<string> bag;
   cout << "Testing the Link-Based Bag:" << endl;
   cout << "isEmpty: returns " << bag.isEmpty()
   << "; should be 1 (true)" << endl;
   displayBag(bag);

   string items[] = {"one", "two", "three", "four", "five", "one"};
   cout << "Add 6 items to the bag: " << endl;
   for (int i = 0; i < 6; i++)
   {
       bag.add(items[i]);
   } // end for

   displayBag(bag);

   cout << "isEmpty: returns " << bag.isEmpty()
   << "; should be 0 (false)" << endl;
  
   cout << "getCurrentSize: returns " << bag.getCurrentSize()
   << "; should be 6" << endl;

   cout << "Try to add another entry: add("extra") returns "
   << bag.add("extra") << endl;

   cout << "contains("three"): returns " << bag.contains("three")
   << "; should be 1 (true)" << endl;
   cout << "contains("ten"): returns " << bag.contains("ten")
   << "; should be 0 (false)" << endl;
   cout << "getFrequencyOf("one"): returns "
   << bag.getFrequencyOf("one") << " should be 2" << endl;
   cout << "remove("one"): returns " << bag.remove("one")
   << "; should be 1 (true)" << endl;
   cout << "getFrequencyOf("one"): returns "
   << bag.getFrequencyOf("one") << " should be 1" << endl;
   cout << "remove("one"): returns " << bag.remove("one")
   << "; should be 1 (true)" << endl;
   cout << "remove("one"): returns " << bag.remove("one")
   << "; should be 0 (false)" << endl;
   cout << endl;

   displayBag(bag);

   cout << "After clearing the bag, ";
   bag.clear();

   cout << "isEmpty: returns " << bag.isEmpty()
   << "; should be 1 (true)" << endl;
} // end bagTester

void newMethodTester()
{
   LinkedBag<string> bag;
   LinkedBag<string> bag2;

    string items[] = {"the", "fox", "fox", "fox", "fox", "fox"};   
   //string items[] = {"one", "two", "three", "four", "five", "one"};
   for (int i = 0; i < 6; i++)
   {
       bag.add(items[i]);
   } // end for
   displayBag(bag);
  
   string items2[]= {"the", "quick", "fox", "fox"};
   //string items2[] = {"one", "shell", "beach", "two"};
   for (int i = 0; i < 4; i++)
   {
       bag2.add(items2[i]);
   } // end for
   displayBag(bag2);

   LinkedBag<string> unionResult = bag.bagUnion(bag2);
   LinkedBag<string> intersectResult = bag.intersect(bag2);
   LinkedBag<string> diffResult = bag.difference(bag2);
   LinkedBag<string> diffResult2 = bag.trueDifference(bag2);
   LinkedBag<string> intersectResult2 = bag.trueIntersect(bag2);
  
   displayBag(unionResult);
   displayBag(intersectResult);
   displayBag(intersectResult2);
   displayBag(diffResult);
   displayBag(diffResult2);
}

int main()
{
   //copyConstructorTester();
   //bagTester();
   newMethodTester();
  
   return 0;
} // end main


LinkedBag.cpp
#include "LinkedBag.h"
#include "Node.h"
#include <cstddef>

template<class ItemType>
LinkedBag<ItemType>::LinkedBag() : headPtr(nullptr), itemCount(0)
{
} // end default constructor

template<class ItemType>
LinkedBag<ItemType>::LinkedBag(const LinkedBag<ItemType>& aBag)
{
   itemCount = aBag.itemCount;
   Node<ItemType>* origChainPtr = aBag.headPtr; // Points to nodes in original chain

   if (origChainPtr == nullptr)
      headPtr = nullptr; // Original bag is empty
   else
   {
      // Copy first node
      headPtr = new Node<ItemType>();
      headPtr->setItem(origChainPtr->getItem());
    
      // Copy remaining nodes
      Node<ItemType>* newChainPtr = headPtr;      // Points to last node in new chain
      origChainPtr = origChainPtr->getNext();     // Advance original-chain pointer
    
      while (origChainPtr != nullptr)   // origChainPtr is used as our counting pointer to traverse
       // the old chain
      {
         // Get next item from original chain
         ItemType nextItem = origChainPtr->getItem();
            
         // Create a new node containing the next item
         Node<ItemType>* newNodePtr = new Node<ItemType>(nextItem);
       
         // Link new node to end of new chain
         newChainPtr->setNext(newNodePtr);
       
         // Advance pointer to new last node
         newChainPtr = newChainPtr->getNext();

         // Advance original-chain pointer
         origChainPtr = origChainPtr->getNext();
      } // end while
    
      newChainPtr->setNext(nullptr);              // Flag end of chain
   } // end if
} // end copy constructor

template<class ItemType>
LinkedBag<ItemType>::~LinkedBag()
{
   clear();
} // end destructor

template<class ItemType>
bool LinkedBag<ItemType>::isEmpty() const
{
   return itemCount == 0;
} // end isEmpty

template<class ItemType>
int LinkedBag<ItemType>::getCurrentSize() const
{
   return itemCount;
} // end getCurrentSize

template<class ItemType>
bool LinkedBag<ItemType>::add(const ItemType& newEntry)
{
   // Add to beginning of chain: new node references rest of chain;
   // (headPtr is null if chain is empty)      
   Node<ItemType>* nextNodePtr = new Node<ItemType>();
   nextNodePtr->setItem(newEntry);
   nextNodePtr->setNext(headPtr); // New node points to chain
//   Node<ItemType>* nextNodePtr = new Node<ItemType>(newEntry, headPtr); // alternate code

   headPtr = nextNodePtr;          // New node is now first node
   itemCount++;

   return true;
} // end add

template<class ItemType>
vector<ItemType> LinkedBag<ItemType>::toVector() const
{
   vector<ItemType> bagContents;
   Node<ItemType>* curPtr = headPtr;
   int counter = 0;
   while ((curPtr != nullptr) && (counter < itemCount))
   {
       bagContents.push_back(curPtr->getItem());
      curPtr = curPtr->getNext();
      counter++;
   } // end while

   return bagContents;
} // end toVector

template<class ItemType>
bool LinkedBag<ItemType>::remove(const ItemType& anEntry)
{
   Node<ItemType>* entryNodePtr = getPointerTo(anEntry);
   bool canRemoveItem = !isEmpty() && (entryNodePtr != nullptr);
   if (canRemoveItem)
   {
      // Copy data from first node to located node
      entryNodePtr->setItem(headPtr->getItem());
    
      // Delete first node
      Node<ItemType>* nodeToDeletePtr = headPtr;
      headPtr = headPtr->getNext();
    
      // Return node to the system
      nodeToDeletePtr->setNext(nullptr);
      delete nodeToDeletePtr;
      nodeToDeletePtr = nullptr;
    
      itemCount--;
   } // end if

   return canRemoveItem;
} // end remove

template<class ItemType>
void LinkedBag<ItemType>::clear()
{
   Node<ItemType>* nodeToDeletePtr = headPtr;
   while (headPtr != nullptr)
   {
      headPtr = headPtr->getNext();

      // Return node to the system
      nodeToDeletePtr->setNext(nullptr);
      delete nodeToDeletePtr;
    
      nodeToDeletePtr = headPtr;
   } // end while
   // headPtr is nullptr; nodeToDeletePtr is nullptr

   itemCount = 0;
} // end clear

template<class ItemType>
int LinkedBag<ItemType>::getFrequencyOf(const ItemType& anEntry) const
{
   int frequency = 0;
   int counter = 0;
   Node<ItemType>* curPtr = headPtr;
   while ((curPtr != nullptr) && (counter < itemCount))
   {
      if (anEntry == curPtr->getItem())
      {
         frequency++;
      } // end if
    
      counter++;
      curPtr = curPtr->getNext();
   } // end while

   return frequency;
} // end getFrequencyOf

template<class ItemType>
bool LinkedBag<ItemType>::contains(const ItemType& anEntry) const
{
   return (getPointerTo(anEntry) != nullptr);
} // end contains

template<class ItemType>
LinkedBag<ItemType> LinkedBag<ItemType>::bagUnion(const LinkedBag& input) const{
   // make a new LinkedBag that will hold the union
   // copy input values into the union bag using copy constructor
   LinkedBag<ItemType> theUnion = LinkedBag(input);
   // add the caller values
   Node<ItemType>* origChainPtr = headPtr; // Points to nodes in original chain
   while (origChainPtr != nullptr) // only add if second chain isn't empty.
   {
      // Copy first node
       theUnion.add(origChainPtr->getItem());
       origChainPtr=origChainPtr->getNext();
   }
   return theUnion;
   }

//Lab 4-2
template<class ItemType>
LinkedBag<ItemType> LinkedBag<ItemType>::intersect(const LinkedBag& input) const{
   // make a new LinkedBag that will hold the intersect
   LinkedBag<ItemType> theIntersect;
   // traverse the existing linked list
   Node<ItemType>* callerPtr = headPtr;
   Node<ItemType>* paramPtr = input.headPtr;
   while (callerPtr != nullptr)
   {
       //cout<<"caller: "<<callerPtr->getItem()<<endl;
       while(paramPtr != nullptr){
       // compare item entries
       //cout<<"input: "<<paramPtr->getItem()<<endl;
           if(callerPtr->getItem() == paramPtr->getItem()){ //if there's a match
               //add to intersect
               theIntersect.add(callerPtr->getItem());
               // stop looking for this value
               paramPtr = paramPtr->getNext();
               break;
           }
           //advance to next item in paramPtr
           paramPtr = paramPtr->getNext();
       }
   //reset paramPtr
   paramPtr = input.headPtr;
   //advance to next item in callerPtr
   callerPtr = callerPtr->getNext();
   }
return theIntersect;
}

//Lab 4-2 extension: true intersect
template<class ItemType>
LinkedBag<ItemType> LinkedBag<ItemType>::trueIntersect(const LinkedBag& input) const{
   // make a new LinkedBag that will hold the intersect
   LinkedBag<ItemType> theIntersect;
   // traverse the existing linked list
   Node<ItemType>* callerPtr = headPtr;
   Node<ItemType>* paramPtr = input.headPtr;
   int callerCount = 0;
   int inputCount = 0;
   int intersect = 0;
   int sectCount = 0;
   while (callerPtr != nullptr)
   {
       //cout<<"caller: "<<callerPtr->getItem()<<endl;
       while(paramPtr != nullptr){
       // compare item entries
       //cout<<"input: "<<paramPtr->getItem()<<endl;
           if(callerPtr->getItem() == paramPtr->getItem()){ //if there's a match
           //check to see if already in intersect
               sectCount = theIntersect.getFrequencyOf(callerPtr->getItem());
               // if already in difference, break
               if(sectCount > 0)
                   break;
               callerCount = getFrequencyOf(callerPtr->getItem());
               //cout<<"callerCount is: "<<callerCount<<endl;
               inputCount = input.getFrequencyOf(paramPtr->getItem());
               //cout<<"inputCount is: "<<inputCount<<endl;
               if(callerCount < inputCount)
                   intersect = callerCount;
               else if (inputCount < callerCount)
                   intersect = inputCount;
               else
                   // they're the same
                   intersect = inputCount;
               //add to intersect
               for(int i=0; i<intersect; i++)
                   theIntersect.add(callerPtr->getItem());
               // stop looking for this value
               paramPtr = paramPtr->getNext();
               break;
           }
           //advance to next item in paramPtr
           paramPtr = paramPtr->getNext();
       }
   //reset paramPtr
   paramPtr = input.headPtr;
   //advance to next item in callerPtr
   callerPtr = callerPtr->getNext();
   }
return theIntersect;
}

//Lab 4-3
template<class ItemType>
LinkedBag<ItemType> LinkedBag<ItemType>::difference(const LinkedBag& input) const{
   // make a new LinkedBag that will hold the difference
   LinkedBag<ItemType> theDiff;
   // traverse the existing linked list
   Node<ItemType>* callerPtr = headPtr;
   Node<ItemType>* paramPtr = input.headPtr;
   while (callerPtr != nullptr)
   {
       while(paramPtr != nullptr){
       // compare item entries
       if(callerPtr->getItem() == paramPtr->getItem()){
           //do nothing and stop looking
           break;
       }
       //if we get to the end of input and don't find it.
       if(paramPtr->getNext() == nullptr){
           // items are not equivalent.
           //add to difference
           theDiff.add(callerPtr->getItem());
           break;
       }
       //advance to next item in paramPtr
       paramPtr = paramPtr->getNext();
       }
   //reset paramPtr
   paramPtr = input.headPtr;
   //advance to next item in callerPtr
   callerPtr = callerPtr->getNext();

   }
return theDiff;


}

//Lab 4-3 extension- true difference
template<class ItemType>
LinkedBag<ItemType> LinkedBag<ItemType>::trueDifference(const LinkedBag& input) const{
   // make a new LinkedBag that will hold the difference
   LinkedBag<ItemType> theDiff;
   // traverse the existing linked list
   Node<ItemType>* callerPtr = headPtr;
   Node<ItemType>* paramPtr = input.headPtr;
   int callerCount = 0;
   int inputCount = 0;
   int diff = 0;
   int diffCount = 0;
   while (callerPtr != nullptr)
   {
       while(paramPtr != nullptr){
       // compare item entries
           if(callerPtr->getItem() == paramPtr->getItem()){
               //check to see if already in difference
               diffCount = theDiff.getFrequencyOf(callerPtr->getItem());
               // if already in difference, break
               if(diffCount > 0)
                   break;
               callerCount = getFrequencyOf(callerPtr->getItem());
               //cout<<"callerCount is: "<<callerCount<<endl;
               inputCount = input.getFrequencyOf(paramPtr->getItem());
               //cout<<"inputCount is: "<<inputCount<<endl;
               diff = callerCount - inputCount;
               //cout<<"diff is: "<<diff<<endl;
               if (diff < 0)
                   diff = 0;
               if (diff > 0){
                   for(int i=0; i<diff; i++)
                       theDiff.add(callerPtr->getItem());
               }
               break;
  
           }      
           //if we get to the end of input and don't find it.
           if(paramPtr->getNext() == nullptr){
               // items are not equivalent.
               //add to difference
               theDiff.add(callerPtr->getItem());
               break;
           }
       //advance to next item in paramPtr
       paramPtr = paramPtr->getNext();
       }
   //reset paramPtr
   paramPtr = input.headPtr;
   //advance to next item in callerPtr
   callerPtr = callerPtr->getNext();

   }
return theDiff;
}

// private
// Returns either a pointer to the node containing a given entry
// or the null pointer if the entry is not in the bag.
template<class ItemType>
Node<ItemType>* LinkedBag<ItemType>::getPointerTo(const ItemType& anEntry) const
{
   bool found = false;
   Node<ItemType>* curPtr = headPtr;

   while (!found && (curPtr != nullptr))
   {
      if (anEntry == curPtr->getItem())
         found = true;
      else
         curPtr = curPtr->getNext();
   } // end while

   return curPtr;
} // end getPointerTo

LinkedBag.h
#ifndef _LINKED_BAG
#define _LINKED_BAG

#include "BagInterface.h"
#include "Node.h"

template<class ItemType>
class LinkedBag : public BagInterface<ItemType>
{
private:
   Node<ItemType>* headPtr; // Pointer to first node
   int itemCount;           // Current count of bag items

   // Returns either a pointer to the node containing a given entry
   // or the null pointer if the entry is not in the bag.
   Node<ItemType>* getPointerTo(const ItemType& target) const;

public:
   LinkedBag();
   LinkedBag(const LinkedBag<ItemType>& aBag); // Copy constructor
   virtual ~LinkedBag();                       // Destructor should be virtual
   int getCurrentSize() const;
   bool isEmpty() const;
   bool add(const ItemType& newEntry);
   bool remove(const ItemType& anEntry);
   void clear();
   bool contains(const ItemType& anEntry) const;
   int getFrequencyOf(const ItemType& anEntry) const;
   vector<ItemType> toVector() const;
   LinkedBag<ItemType>bagUnion(const LinkedBag& input) const; // Lab 4-1
   LinkedBag<ItemType> intersect(const LinkedBag& input) const; //Lab 4-2
   LinkedBag<ItemType> trueIntersect(const LinkedBag& input) const;
   LinkedBag<ItemType> difference(const LinkedBag& input) const; // Lab 4-3
   LinkedBag<ItemType> trueDifference(const LinkedBag& input) const;
}; // end LinkedBag

#include "LinkedBag.cpp"
#endif

Node.cpp
#ifndef _LINKED_BAG
#define _LINKED_BAG

#include "BagInterface.h"
#include "Node.h"

template<class ItemType>
class LinkedBag : public BagInterface<ItemType>
{
private:
   Node<ItemType>* headPtr; // Pointer to first node
   int itemCount;           // Current count of bag items

   // Returns either a pointer to the node containing a given entry
   // or the null pointer if the entry is not in the bag.
   Node<ItemType>* getPointerTo(const ItemType& target) const;

public:
   LinkedBag();
   LinkedBag(const LinkedBag<ItemType>& aBag); // Copy constructor
   virtual ~LinkedBag();                       // Destructor should be virtual
   int getCurrentSize() const;
   bool isEmpty() const;
   bool add(const ItemType& newEntry);
   bool remove(const ItemType& anEntry);
   void clear();
   bool contains(const ItemType& anEntry) const;
   int getFrequencyOf(const ItemType& anEntry) const;
   vector<ItemType> toVector() const;
   LinkedBag<ItemType>bagUnion(const LinkedBag& input) const; // Lab 4-1
   LinkedBag<ItemType> intersect(const LinkedBag& input) const; //Lab 4-2
   LinkedBag<ItemType> trueIntersect(const LinkedBag& input) const;
   LinkedBag<ItemType> difference(const LinkedBag& input) const; // Lab 4-3
   LinkedBag<ItemType> trueDifference(const LinkedBag& input) const;
}; // end LinkedBag

#include "LinkedBag.cpp"
#endif

Node.h

#ifndef _NODE
#define _NODE

template<class ItemType>
class Node
{
private:
   ItemType        item; // A data item
   Node<ItemType>* next; // Pointer to next node

public:
   Node();
   Node(const ItemType& anItem);
   Node(const ItemType& anItem, Node<ItemType>* nextNodePtr);
   void setItem(const ItemType& anItem);
   void setNext(Node<ItemType>* nextNodePtr);
   ItemType getItem() const ;
   Node<ItemType>* getNext() const ;
}; // end Node

#include "Node.cpp"
#endif

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