Linked Queue.txt

#include <iostream>
#include <cassert>
using namespace std;
template<class t>
class linkedQueue
{
private:
	struct Node
	{
		t item;
		Node *next;
	};
	int length;
	Node *frontPtr, *rearPtr;

public:
	
linkedQueue():frontPtr(NULL), rearPtr(NULL), length(0)
	{}
	bool isEmpty()
	{
		return (length == 0);
	}

	void dequeue()
	{
		if (isEmpty())
			cout << "Empty Queue" << endl;
		else if (length == 1)
		{
			delete frontPtr;
			rearPtr = NULL;
			length = 0;
		}
		else
		{
			Node *current = frontPtr;
			frontPtr = frontPtr->next;
			delete current;//free(current)
			length--;
		}
	}

	void enqueue(t item)
	{
		Node *newNode = new Node;
		newNode->item = item;
		newNode->next = NULL;

		if (length == 0)
			rearPtr = frontPtr = newNode;
		else
		{
			rearPtr->next = newNode;
			rearPtr = newNode;
		}
		length++;
	}

	t front()
	{
		assert(!isEmpty());
		return frontPtr->item;
	}

	t rear()
	{
		assert(!isEmpty());
		return rearPtr->item;
	}

	void clearQueue()
	{
		Node *current;

		while (frontPtr != NULL)
		{
			current = frontPtr;
			frontPtr = frontPtr->next;
			delete current;
		}
		rearPtr = NULL;
		length = 0;
	}
	void display()
	{
		Node*cur = frontPtr;
		cout << "Item in the queue :[ ";
		while (cur!=NULL)
		{
			cout << cur->item<<" ";
			cur = cur->next;
		}cout << "]" << endl;
	}

	void search(t item)
	{
		Node*cur = frontPtr;
		bool flag = true;
		while (cur != NULL)
		{
			if (cur->item == item)
			{
				cout << "the item :" << item << " found" << endl;
				flag = false;
				break;
			}
			cur = cur->next;
		}
		if(flag)
			cout << "the item : " << item << " not found" << endl;

	}

};

int main()
{
	linkedQueue<int>q1;

	for (int i = 1; i <= 20; i++)
		q1.enqueue(i);

	cout << q1.front() << endl;
	cout << q1.rear() << endl;
	q1.display();
	return 0;
}