LinkedList.cpp

/*
*
*Created by: Mir Sahib
*Aug 18, 2017
*8:15:46 PM
*
*/
#include <iostream>
#include "list.h"

using namespace std;
typedef struct node{
	int data;
	node* next;
}* nodePtr;

List::List(){
	head = NULL;
	curr = NULL;
	temp= NULL;
	prev = NULL;
}
//general function
List::node *List::getHead(){
    return head;
}
List::node *List::getPrev(){
	return prev;
}

void List::setPrev(nodePtr newPrev){
	prev = newPrev;
}
void List::setHead(nodePtr newHead){
    head = newHead;
}
void List::addNode(int addData){
	temp = new node;
	temp->data = addData;
	temp->next = NULL;
	if(head!=NULL){
		curr = head;
		while(curr->next!=NULL){
			curr = curr->next;
		}
		curr->next = temp;
	}else{
		head=temp;
	}
}
void List::insertNodeToHead(int newData){
	temp = new node;
	temp->data = newData;
	temp->next = head;
	head = temp;
}
void List::deleteNthPosition(int pos){
	int length = lengthOfTheList();
	if(pos>length){
		cout<<"Invalid index"<<endl;
	}else{
		if(pos==1){
			temp = head;
			head = temp->next;
			delete temp;
		}else{
			curr = head;
			for(int i=0;i<pos-2;i++){
				curr=curr->next;
			}
			temp = curr->next;
			curr->next = temp->next;
			delete temp;
		}
	}
}
void List::insertToNthPosition(int pos,int newData){
	temp = new node;
	temp->data = newData;
	temp->next = NULL;
	if(pos==1){
		temp->next=head;
		head=temp;
	}else{
		curr = head;
	for(int i=0;i<pos-2;i++){
		curr=curr->next;
	}
		temp->next = curr->next;
		curr->next=temp;
	}
}
void List::reverseList(){
	curr = head;
	while(curr!=NULL){
		temp = curr->next;
		curr->next = prev;
		prev = curr;
		curr=temp;
	}
	head = prev;
}
//recursive function
void List::printRecurs(nodePtr newNode){
	if(newNode!=NULL){
		cout<<newNode->data<<" ";
		printRecurs(newNode->next);
	}
}
void List::reverseRecurs(nodePtr newNode){
	if(newNode==NULL){
        newNode = NULL;
	}else if(newNode->next==NULL){
        head = newNode;
	}else{
        temp = newNode->next;
        newNode->next=NULL;
        reverseRecurs(temp);
        temp->next=newNode;
        temp = newNode;
	}

}
//miscellaneous function
int List::lengthOfTheList(){
	temp = head;
	int length = 0;
	while(temp!=NULL){
		temp=temp->next;
		length++;
	}
	return length;
}

void List::printNode(){
	temp = head;
	cout<<"List is: ";
	while(temp!=NULL){
		cout<<temp->data<<" ";
		temp=temp->next;
	}
	cout<<endl;
}


int main(){

	int limit,num;
	List myList;
	cout<<"How many number to print"<<endl;
	cin>>limit;
	for(int i=0;i<limit;i++){
		cout<<"Enter Number"<<endl;
		cin>>num;

		myList.insertNodeToHead(num);
		myList.printNode();
	}
	myList.insertToNthPosition(1,14);
	cout<<"Inserting node at nth position"<<endl;
	myList.printNode();
	cout<<"delete node at nth position"<<endl;
	myList.deleteNthPosition(2);
	myList.printNode();
	cout<<"Reverse List"<<endl;
	myList.reverseList();
	myList.printNode();
	cout<<"Recursive printing"<<endl;
	myList.printRecurs(myList.getHead());
	cout<<"\nRecursive reverse"<<endl;
	myList.reverseRecurs(myList.getHead());
	myList.printRecurs(myList.getHead());


	return 0;
}