sLinkedList.cpp

/******************************
  	sLinkedList.cpp
    Auther:Syed Zain Ul hasan
  *****************************/
#include <iostream>
using namespace std;

//Node Structure
struct Node{
	int data;
	Node* next;
};
//Link List Class
class LinkList{
private:
	Node* first;
	Node* last;

	int size;
public:
	LinkList():size(0){
		first = last = NULL;
	};

	//Inserts Item at the end
	void push_back(int val){

		//Make a Temp Node And Fill With Data
		Node* tmp = new Node();
		tmp->data = val;
		tmp->next = NULL;

		//If List is empty make temp Node as First
		if (first == NULL){
			first = tmp;
			last = tmp;
		}
		else {//Insert Node into last
			last->next = tmp;
			last = tmp;
		}

		size++;
	}

	//Inserts the item at the start
	void push_front(int val){
		//Make a Temp Node And Fill With Data
		Node* tmp = new Node();
		tmp->data = val;

		//If List is empty make temp Node as First
		if (first == NULL){
			tmp->data = NULL;
			first = tmp;
			last = tmp;
		}
		else {//insert First node into temp
			tmp->next = first;
			first= tmp;
		}

		size++;
	}

	//delete item from last
	void pop_back(){
		if (first == NULL)//means empty
			return;
		else
		{
			if (first == last)// only have one Item so
				first = last = NULL;

			else{
				Node* tmp = first;
				while (tmp->next != last)//Move one before Last Item
					tmp = tmp->next;

				delete last;
				last = tmp;

			}
			size--;
		}

	}

	//delete item from start
	void pop_front(){
		if (first == NULL)//means empty
			return;
		else{
			if (first == last)// only have one Item so
				first = last = NULL;

			else{
				Node* tmp = first->next;//simple first's next will becomes the first Node
				delete first;
				first = tmp;
			}
			size--;
		}
	}



void Remove(int data) {
     Node *tmp = first;
     if ( tmp == NULL )
          return;
     if ( tmp->next == NULL ) {
          delete tmp;
          first = NULL;
     }
     else {
          Node *prev;
          do {
              if ( tmp->data == data ) break;
              prev = tmp;
              tmp = tmp->next;
          } while ( tmp != NULL );
     prev->next=tmp->next;
     delete tmp;
     }
}
void insert(int data, int pos)
{
  Node* prev = new Node();
  Node* curr = new Node();
  Node* newNode = new Node();
  newNode->data = data;

  int tempPos = 0;   // Traverses through the list

  curr = first;      // Initialize current to first;
  if(first != NULL)
  {
    while(curr->next != NULL && tempPos != pos)
    {
        prev = curr;
        curr = curr->next;
        tempPos++;
    }
    if(pos==0)
    {
       push_front(data);
    }
    else if(curr->next == NULL && pos == tempPos+1)
    {
      push_back(data);
    }
    else if(pos > tempPos+1)
      cout << " Invalid Position " << endl;
    else
    {
        prev->next = newNode;
        newNode->next = curr;

    }
 }
 else
 {
    first = newNode;
    newNode->next=NULL;
 }
}

	void displayAll(){
		Node* tmp = first;
		while (tmp!=last){
			cout << tmp->data << " ";
			tmp = tmp->next;
		}
		cout <<tmp->data<< endl;//last item
	}

	int Size(){
		return size;
	}

	bool isEmpty(){
		if (first == NULL)
			return true;
		else
			return false;
	}

};

int main(){

	LinkList* l=new LinkList();

	//Insert some Items at the   end
	l->push_back(5);
	l->push_back(6);
	l->push_back(7);
	l->push_back(8);
	//Insert some Items at the   start
	l->push_front(10);
	l->push_front(11);
	l->push_front(12);
	l->push_front(13);

	cout << "Items are  : ";
	l->displayAll();

	//delete an item from last
	l->pop_back();
	//delete an item from front
	l->pop_front();

	cout << "Items after deleting from back & front  : ";
	l->displayAll();



	return 0;
}