4.pres_sec _club

//SINGLY LINKEDLIST

//use do while to keep adding members.

//In dipslay, seperate display for pres and sec isnt happening.

//Node swap isnt happening

//Sorting is done . not merging

#include <iostream>
using namespace std;

class node
{
	string name;
	int prn;
	node* next;
public:
	node()
	{
		name ="";
		prn = 0;
	}
	friend class ll;
};

class ll
{
public:
	node* head;
	node* tail;

	ll()
	{
		head = NULL;
		tail = NULL;
	}
	void insert_front();
	void insert_between(int key);
	void insert_back();
	void del_front();
	void del_between(int key);
	void del_back();
	void display();
	void count();
	void disp_rev(node* start);
	void concate(node* ahead, node* atail, node* bhead);
	void sort();
};

void ll::insert_front()
{
	node* nn = new node;
	cout << "Enter President Details:" << endl;
	cout << "Enter Name:" << endl;
	cin >> nn->name;
	cout << "Enter PRN:" << endl;
	cin >> nn->prn;
	nn->next = NULL;

	if (head == NULL && tail == NULL)//empty
	{
		head = nn;
		tail = nn;
		cout << "---Inserted in Empty Linked List---" << endl;
	}

	else//not empty
	{
		nn->next = head;
		head = nn;
		cout << "---Inserted At Start---" << endl;
	}
}

void ll::insert_back()
{
	node* nn = new node;
	cout << "Enter Secreatary Details:" << endl;
	cout << "Enter Name:" << endl;
	cin >> nn->name;
	cout << "Enter PRN:" << endl;
	cin >> nn->prn;
	nn->next = NULL;

	if (head == NULL && tail == NULL)//empty
	{
		head = nn;
		tail = nn;
		cout << "---Inserted in Empty LINKED List---" << endl;
	}
	else//not empty
	{
		tail->next = nn;
		tail = nn;
		cout << "---Inserted at End---" << endl;
	}
}

void ll::insert_between(int key)
{
	//3cases

	node* nn = new node;
	cout << "Enter Member Details:" << endl;
	cout << "Enter Name:" << endl;
	cin >> nn->name;
	cout << "Enter PRN:" << endl;
	cin >> nn->prn;
	nn->next = NULL;

	int flag = 0;

	if (head == NULL && tail == NULL)//empty
	{
		head = nn;
		tail = nn;
		cout << "---Inserted in Empty Linked list" << endl;
		cout << "---Currently This Member is Both Pres and Sec" << endl;
	}
	
	else if (flag == 0)
	{
		node* start = head;
		while (start != NULL)
		{
			if (start->prn == key)
				flag++;

			start = start->next;
		}

		if (flag == 0)//invalid prn
		{
			cout << "---Invalid PRN---" << endl;
			cout << "---Insertion Not possible---" << endl;
		}

		else if (tail->prn == key)//inserting at last
		{
			tail->next = nn;
			tail = nn;
			cout << "---Inserted at End---" << endl;
			cout << "---This Member became Secretary---" << endl;
		}
		else //inserting in valid prn
		{
			node* temp = head;
			node* temp2;

			while (temp->prn != key && temp != NULL)
			{
				temp = temp->next;
			}

			temp2 = temp->next;

			temp->next = nn;
			nn->next = temp2;

			cout << "---Inserted Member at proper Position---" << endl;
		}
	}
}

void ll::del_front()
{
	//2 cases
	if (head == NULL && tail == NULL)//empty
		cout << "---Nothing To delete---" << endl;

	else//non empty
	{
		node* temp = head;
		head = head->next;
		delete(temp);
	}
}

void ll::del_between(int key)
{
	int flag = 0;

	if (head == NULL && tail == NULL)//empty
	{
		cout << "---Nothing to Delete---" << endl;
	}
	else if (flag == 0)
	{
		node* start = head;
		while (start != NULL)
		{
			if (start->prn == key)
				flag++;

			start = start->next;
		}
		if (flag == 0)
		{
			cout << "---Invalid PRN---" << endl;
			cout << "---No deletion Possible" << endl;
		}
		else if (tail->prn == key && head!=tail)//delete at end with multiple elements
		{
			node* temp = head;
			while (temp->next != tail)
			{
				temp = temp->next;
			}
			tail = temp;
			temp = temp->next;
			tail->next = NULL;
			delete(temp);
			cout << "---DEleted at end---" << endl;
		}
		else if (head->prn == key)//del at start with single and multiple elements
		{
			node* temp = head;
			head = head->next;
			temp->next = NULL;
			delete(temp);
			cout << "---Deleted at start---" << endl;
		}

		else//proper deleteion from between
		{
			node* temp = head;
			node* temp2 = head;
			while (temp->prn != key)
			{
				temp2 = temp;
				temp = temp->next;
			}
			temp2->next = temp->next;
			temp->next = NULL;
			delete(temp);
			cout << "---Deleted from proper position---" << endl;
		}
	}
}
void ll::del_back()
{
	//3 cases

	if (head == NULL && tail == NULL)//empty
	{
		cout << "---Nothing to Delete--- " << endl;
	}

	else if (head->next == NULL)//only 1 element
	{
		node* temp=tail;
		delete(temp);
		head = tail = NULL; //very imp
		cout << "---Deleted the only Element in Linked List---" << endl;
	}

	else
	{
		node* temp = head;
		node* temp2 = head;
		while (temp->next != NULL)
		{
			temp2 = temp;
			temp = temp->next;
		}
		tail = temp2;
		tail->next = NULL; //very imp
		delete(temp);
		cout << "---Deleted at End----" << endl;
	}
}

void ll::concate(node* ahead, node* atail, node* bhead)
{
	head = ahead;
	atail->next = bhead;
}

void ll::sort()
{
	/*string temp_name;
	int temp_prn;
	node* temp3 = head;
	node* temp1;
	node* temp2;

	for (temp1 = head; temp1 != NULL; temp1 = temp1->next)//for(int i=0;i<n-1;i++)
	{
		for (temp2 = head; temp2->next!= NULL; temp2 = temp2->next) //for(j=0;j<n-1;j++)
		{
			temp2->next = temp3;

			if (temp2->prn > temp3->prn)
			{
				

				temp_prn = temp2->prn;
				temp2->prn = temp3->prn;
				temp3->prn = temp_prn;

				temp_name = temp2->name;
				temp2->name = temp3->name;
				temp3->name= temp_name;

			}
		}
	}*/

	node* temp1;
	node* temp2;
	node* temp3;
	

	for (temp1 = head; temp1->next != NULL; temp1 = temp1->next)//for(i=0;i<n-1;i++)
	{
		for (temp2 = head; temp2->next != NULL; temp2 = temp2->next)//for(j=0;j<n-1;j++)
		{
			//BY DATA SWAP 
			temp3 = temp2->next;
			if (temp2->prn > temp3->prn)
			{

				swap(temp2->prn, temp3->prn);

				swap(temp2->name, temp3->name);
			}
		}
	}
}

void ll::display()
{
	cout << "\n\tDisplaying Members" << endl;
	node* temp = head;
	if (temp == NULL)
	{
		cout << "---Nothing to display---" << endl;
		cout << "---Empty linked list---" << endl;
	}
	while (temp != NULL)
	{
		cout <<"Name:"<<temp->name << endl;
		cout << "PRN:" << temp->prn << endl;
		temp = temp->next;
	}
}

void ll::disp_rev(node* start)
{
	if (start->next == NULL)
	{
		cout << "Name: " << start->name << endl;
		cout << "PRN: " << start->prn << endl;
	}
	else
	{
		disp_rev(start->next);

		cout << "Name: " << start->name << endl;
		cout << "PRN: " << start->prn << endl;
	}
}

void ll::count()
{
	int count = 0;
	node* start = head;
	while (start != NULL)
	{
		count++;
		start = start->next;
	}
	cout << "Total Members: " << count << endl;
}

int main()
{
	int ch, ch2;
	int prn,prn2,prn3;
	ll a;

	cout << "\n\tDIV A" << endl;

	do
	{
		cout << "Select Your Choice" << endl;
		cout << "\n\t1.Add President" << endl;
		cout << "\n\t2.Add Member" << endl;
		cout << "\n\t3.Add Secretary" << endl;
		cout << "\n\t4.Delete President" << endl;
		cout << "\n\t5.Delete Member" << endl;
		cout << "\n\t6.Delete Secretary" << endl;
		cout << "\n\t7.Display Club Member" << endl;
		cout << "\n\t8.Display Club Members in Reverse" << endl;
		cout << "\n\t9.Total Members Count" << endl;
		cout << "\n\t10.Exit" << endl;
		cin >> ch;

		switch (ch)
		{
		case 1:
			a.insert_front();
			break;

		case 2:
			cout << "Enter PRN after which you want ?" << endl;
			cin >> prn;
			a.insert_between(prn);
			break;

		case 3:
			a.insert_back();
			break;

		case 4:
			a.del_front();
			break;

		case 5:
			cout << "Enter PRN You want to delete" << endl;
			cin >> prn2;
			a.del_between(prn2);
			break;

		case 6:
			a.del_back();
			break;

		case 7:
			a.display();
			break;

		case 8:
			a.disp_rev(a.head);
			break;

		case 9:
			a.count();
			break;

		case 10:
			cout << "Thank You !!!" << endl;
			break;

		default:cout << "Invalid Choice" << endl;

		}

	} while (ch !=10 );

	cout << "\n\tDIV B " << endl;
	ll b;

	do
	{
		cout << "Select Your Choice" << endl;
		cout << "\n\t1.Add President" << endl;
		cout << "\n\t2.Add Member" << endl;
		cout << "\n\t3.Add Secretary" << endl;
		cout << "\n\t4.Display" << endl;
		cout << "\n\t5.Exit" << endl;
		cin >> ch2;

		switch (ch2)
		{
		case 1:
			b.insert_front();
			break;

		case 2:
			cout << "Enter PRN after which you want ?" << endl;
			cin >> prn3;
			b.insert_between(prn3);
			break;

		case 3:
			b.insert_back();
			break;

		case 4:
			b.display();
			break;

		case 5:cout << "Thank You !!!" << endl;
			break;

		default:cout << "Invalid Choice" << endl;
		
		}

	} while (ch2 != 5);

	ll c;
	cout << "\n\tConcatenating both list" << endl;
	c.concate(a.head, a.tail, b.head);
	c.display();

	cout << "\n\tSorting Combined list" << endl;
	c.sort();
	c.display();

	return 0;
}