Algo2

#include <iostream>
#include <ctime>
#include <stdio.h>
#include <stdlib.h>
using namespace std;
class Node
{
	public:
	int key;
	double d_variable;
	char ch_variable;
	Node** forward;
	//node constructor
	Node(int key, int level)
	{
		this->key = key;
		this->d_variable = rand();
		this->ch_variable = 'T';
		forward = new Node * [level + 1];
		for (int i = 0; i < level + 1; i++)
		{
			forward[i] = NULL;
		}
	}
};
class Skiplist
{
	public:
	Node* HEADER;
	unsigned int MAX_LEVEL;
	int level;
	float PROB;

	//constructor
	Skiplist(int MAX_LEVEL,float PROB)
	{
		this->MAX_LEVEL = MAX_LEVEL;
		this->PROB = PROB;
		level =0;
		HEADER = new Node(-1,MAX_LEVEL);
	}

	//creates new node
	Node* createNode(int key,int level)
	{
		Node* new_node = new Node(key, level);
		return new_node;
	}

	//generates random level including probability
	int randomLevel()
	{
		int level = 0;
		int r = rand() % 100;
		while ((r < PROB * 100) && (level < MAX_LEVEL))
		{
			level++;
			r = rand() % 100;
		}
		return level;
	}

	//inserts one element to the list
	void insertElement(int key)
	{
		Node* current = HEADER;
		Node** update=new Node*[MAX_LEVEL+1];
		for (int i = 0; i <MAX_LEVEL+1; i++)
		{
			update[i] = NULL;
		}
		for (int i = level; i >= 0; i--)
		{
			while ((current->forward[i] != NULL) && (current->forward[i]->key < key))
			{
				current = current->forward[i];
			}
				update[i] = current;

		}
		current = current->forward[0];
		if (current == NULL || current->key != key)
		{
			int r_level = randomLevel();
			if (r_level > level)
			{
				for (int i = level + 1; i < r_level + 1; i++)
				{
					update[i] = HEADER;
				}
				level = r_level;
			}
			Node* new_node = createNode(key, r_level);
			for (int i = 0; i < r_level+1; i++)
			{
				new_node->forward[i] = update[i]->forward[i];
				update[i]->forward[i] = new_node;
			}
			cout << "Yikes" << endl;
		}

	}
	void showAll()
	{
		Node* current = HEADER->forward[0];
		while (current != NULL)
		{
			cout << endl << "Key value:" << current->key<<endl;
			current = current->forward[0];
		}
	}

	//inserts many elements to the list
	void insertManyElements()
	{}

	//finds element in a list
	void findElement()
	{}

	//returns an array of how many nodes there are in particular levels
	int howManyNodes()
	{}

	//shows X first elements
	void showFirstElements()
	{}

	//shows Y last elements
	void showLastElements()
	{}

	//deletes an element from a list
	void deleteElement()
	{}

	//deletes entire list
	void deleteList()
	{}

};
int main()
{
	srand(time(NULL));
	Skiplist my_list(5, 0.5);
	my_list.insertElement(6);
	my_list.insertElement(11);
	my_list.insertElement(4);
	my_list.insertElement(1);
	my_list.insertElement(2);
	my_list.insertElement(20);
	my_list.showAll();


	return 0;
}