fds7

#include <iostream>
#include <string.h>
using namespace std;

//Node
struct node {
int prn;
string name;
struct node *next;
};

//Linked List
class list {
node *head, *temp;
public:
list() {
head = NULL;
}
node *create(int val, string n);
void insertEnd();
void insertBeg();
void deleteAt(int i);
void insertAt(int i);
void display();
int count();
void reverse();
void rev(node t);
node readAt(int i);
void concatenate(list A,list B);
void op();
};

//Create
node* list::create(int val, string n) {
temp = new(struct node);
if (temp == NULL) {
cout<<"Memory Allocation Failed!"<<endl;
return 0;
} else {
temp -> prn = val;
temp -> name = n;
temp -> next = NULL;
return temp;
}
}

//Insert End
void list::insertEnd() {
int val;
string n;
cout<<"Enter PRN: ";
cin>>val;
cout<<"Enter Name: ";
cin>>n;
struct node *t = head;
temp = create(val,n);
if (head == NULL) {
head = temp;
head -> next = NULL;
} else {
while ((t -> next) != NULL) {
t = t -> next;
}
temp -> next = NULL;
t -> next = temp;
cout<<"Element Inserted at Last"<<endl;
}
}

//Insert At
void list::insertAt(int i) {
int val,pos = i - 1,counter = 1;
string n;
struct node *ptr;
struct node *t = head;
while ((t -> next) != NULL) { //loop to count number of items in linked list.
t = t -> next;
counter++;
}
t = head; //traverse pointer is pointed to head again.
if (i == 1) { //equivalent to insert at start.
insertBeg();
} else if (pos > counter || i <= 0) { //if position is greater than the actual linked list.
cout<<"Entered position is out of scope."<<endl;
} else { //insert at required position.
cout<<"Enter PRN: ";
cin>>val;
cout<<"Enter Name: ";
cin>>n;
temp = create(val,n);
while (pos--) {
ptr = t;
t = t -> next;
}
temp -> next = t;
ptr -> next = temp;
cout<<"Member Inserted at Position: "<<i<<endl;
}
}

//Delete At
void list::deleteAt(int i) {
int val,pos = i - 1,counter = 1;
string n;
struct node *ptrl,*ptrr;
struct node *t = head;
while ((t -> next) != NULL) {
t = t -> next;
counter++;
}
t = head;
if (i == 1) {
ptrl = head;
head = head -> next;
delete ptrl;
} else if (pos > counter || i <= 0) {
cout<<"Entered member doesn't exist."<<endl;
} else {
while (pos--) {
ptrl = t;
t = t -> next;
ptrr = t -> next;
}
ptrl -> next = ptrr;
delete t;
cout<<"Member Deleted at Position: "<<i<<endl;
}
}

//Insert Beg
void list::insertBeg() {
int val;
string n;
cout<<"Enter PRN: ";
cin>>val;
cout<<"Enter Name: ";
cin>>n;
//v = val;
struct node *t = head;
temp = create(val,n);
if (head == NULL) {
head = temp;
head -> next = NULL;
} else {
temp -> next = head;
head = temp;
cout<<"We have a New President."<<endl;
}
}

//Display
void list::display() {
temp = head;
cout<<"President: ";
cout<< temp -> prn<<" � "<<temp -> name<<" -> ";
if(temp -> next != NULL) {
temp = temp -> next;
}
while (temp -> next != NULL) {
cout<< temp -> prn<<" � "<<temp -> name<<" -> ";
temp = temp -> next;
}
cout<<"Secretary: ";
cout<< temp -> prn<<" � "<<temp -> name<<" -> ";
cout<<"NULL"<<endl;
}

//Count
int list::count() {
temp = head;
int ct = 0;
while (temp != NULL) {
ct++;
temp = temp -> next;
}
return ct;
}

//Concatenate
void list::concatenate(list A,list B) {
struct node * last,last1;
node t = A.head;
while (t != NULL) {
int val = t -> prn;
string n = t -> name;
temp = create(val,n);
if (head == NULL) {
head = temp;
head -> next = NULL;
last=head;
} else {
//temp -> next = NULL;
last -> next = t;
last=t;
}
t = t -> next;
}
last -> next = B.head;
t = B.head;
while (t != NULL) {
int val = t -> prn;
string n = t -> name;
temp = create(val,n);

		last -> next = temp;
		last= temp;

	t = t -> next;
}
last->next=NULL;

}
//Accept
void list::op() {
while(1) {
int choice;
cout<<"\nEnter: \n1. Add \n2. Delete \n3. Member's Count \n4. Display \n5. Reverse the List \n0. Prev Menu"<<endl;
cin>>choice;
switch(choice) {
case 1: { //Add
char c;
cout<<"\nEnter: \nA. Add President \nB. Add Secretary \nC. Add Member"<<endl;
cin>>c;
switch(c) {
case 'A':
case 'a':{
insertBeg();
break;
}
case 'B':
case 'b': {
insertEnd();
break;
}
case 'C':
case 'c': {
insertAt(2);
break;
}
}
break;
}
case 2: { //Delete
char c;
cout<<"\nEnter: \nA. Delete President \nB. Delete Secretary \nC. Delete Member"<<endl;
cin>>c;
switch(c) {
case 'A': {
deleteAt(1);
cout<<"Club must have a President. Enter Details"<<endl;
insertBeg();
break;
}
case 'B': {
deleteAt(count());
cout<<"Club must have a Secretary. Enter Details"<<endl;
insertEnd();
break;
}
case 'C': {
int j;
cout<<"Enter Position for Deletion"<<endl;
cin>>j;
deleteAt(j);
break;
}
}
break;
}
case 3: { //Count
cout<<"Count: "<<count()<<endl;
break;
}
case 4: { //Display
if (head == NULL) {
cout<<"NULL"<<endl;
break;
} else {
display();
break;
}

		}
		case 5: { //Reverse
			reverse();
			break;
		}
		case 0: { //Prev Menu
			return;
		}
	}
}

}

//Reverse Recursion
void list::rev(node *t) {
if(t -> next != NULL) {
rev (t -> next);
}
if(t == head)
cout<<"Secretary: "<<t -> prn<<" � "<<t -> name<<endl;
else if(t -> next == NULL)
cout<<"President: "<<t -> prn<<" � "<<t -> name<<" -> ";
else
cout<<"Member: "<<t -> prn<<" � "<<t -> name<<" -> ";
}

//Reverse
void list::reverse() {
rev(head);
}

//Read At
node* list::readAt(int i) {
struct node *t = head;
int c = count();
while(c--) {
t = t-> next;
}
}

//Main
int main() {
list L,X,Y;
int c;
while(1) {
cout<<"Enter: \n1. List A \n2. List B \n3. Concatenate\n0. Exit"<<endl;
cin>>c;
switch(c) {
case 1: cout<<"\nList A:"; X.op(); break;
case 2: cout<<"\nList B:"; Y.op(); break;
case 3: L.concatenate(X,Y); L.display(); break;
case 0: return 0;
}
}
}