C++ Pointer Problem: Segmentation Fault Error

I wrote this program to create a circular doubly linked list, however when I compile I continuously get a segmentation fault error and I cannot figure out why. Apologies for the long code!

#include

#include

#include

#include

using namespace std;

struct entry_QB{

string firstName, lastName;

int years[5];

int wins;

entry_QB *next;

entry_QB *prev;

};

void addEntry(string, string, int);

void removeEntry(string, string);

void printEntry();

void deleteList();

entry_QB * searchList(string, string );

entry_QB *HEAD = NULL;

int main(){

ifstream infile("Lab 6_QB_List.txt");

string firstN, lastN;

int year = 0;

while(!infile.eof()){

infile >> firstN;

infile >> lastN;

infile >> year;

addEntry(firstN, lastN, year);

}

int choice = 0;

while(1){

cout << "What function would you like? ";

cout << "Enter 1, to add an entry ";

cout << "Enter 2, to delete an entry ";

cout << "Enter 3, to search for an entry ";

cout << "Enter 4, to print list ";

cout << "Enter 5, to clear list and quit ";

cin >> choice;

if(choice == 1){

cout << "Enter the first name, last name, and year each separated by a space ";

cin >> firstN >> lastN;

cout << "Enter year ";

cin >> year;

addEntry(firstN, lastN, year);

cout << "New entry added/n";

break;

}

else if(choice == 2){

cout << "Enter the first name and last name separated by a space ";

cin >> firstN >> lastN;

removeEntry(firstN, lastN);

cout << "Entry deleted ";

break;

}

else if(choice == 3){

cout << "Enter the first name and last name separated by a space ";

cin >> firstN >> lastN;

searchList(firstN, lastN);

cout << "Entry found ";

break;

}

else if(choice == 4){

cout << "Enter the first name and last name separated by a space ";

cin >> firstN >> lastN >> year;

searchList(firstN, lastN);

break;

}

else if(choice == 5){

deleteList();

break;

}

else{

cout << "Invalid Input ";

}

}

deleteList();

return 0;

}

void addEntry(string firstN, string lastN, int year){ //put the entry at the end of the line

entry_QB *newEntry = new entry_QB;

entry_QB *temp;

entry_QB *TAIL;

if(HEAD == NULL){

HEAD = newEntry;

HEAD -> firstName = firstN;

HEAD -> lastName = lastN;

HEAD -> years[0] = year;

HEAD -> wins = 1;

HEAD -> next = HEAD;

HEAD -> prev = HEAD;

}

else{

temp = searchList(firstN, lastN);

if(temp){

temp -> years[newEntry -> wins] = year;

temp -> wins++;

}

else{

temp = newEntry;

temp -> firstName = firstN;

temp -> lastName = lastN;

temp -> years[0] = year;

temp -> wins = 1;

//for(temp = HEAD; temp != NULL; temp = temp -> next){

for(TAIL = HEAD; TAIL != temp; TAIL = TAIL -> next){

if(temp -> next = HEAD){

//newEntry -> next = HEAD;

//HEAD -> prev = newEntry;

TAIL -> next = temp;

temp -> prev = TAIL;

}

}

temp -> next = HEAD;

HEAD -> prev = temp;

}

}

}

void removeEntry(string firstName, string lastName){

entry_QB *temp = searchList(firstName, lastName);

temp->prev->next = temp->next;

temp->next->prev = temp->prev;

delete temp;

}

void printEntry(){

//

}

void deleteList(){

entry_QB *temp;

temp = HEAD->next;

while(temp){

entry_QB *deleted = temp;

temp = temp->next;

delete deleted;

}

}

entry_QB * searchList(string firstN, string lastN){

entry_QB *temp;

temp = HEAD;

if((temp->firstName == firstN) && (temp->lastName == lastN)){

return temp;

}

for(temp = HEAD->next; temp != HEAD; temp = temp->next){

if((temp->firstName == firstN) && (temp->lastName == lastN)){ //Check if the passed in first name and last name are equal to the current temp entry

return temp; //Returns the address of the correct entry

}

}

temp = NULL;

return temp;

}