//

// Example of use list

//

// Week 3, lecture 3.7

//

#include <iostream>

using namespace std;

typedef struct list_element

{

list_element(int n = 0, list_element* ptr = 0):

data(n), next(ptr) {};

int data;

list_element *next;

} list_element;

class list

{

public:

list():head(0),cursor(0) { cout << "default constructor\n"; }

// list(list_element *h = 0, list_element *c = 0):head(h),cursor(c)

// { cout << "default constructor\n"; }

list(const int *arr, int sz); // move elements from an array

~list(); // destructor

void prepend(int n); // add an element before head

void add(int n); // add an element at the end of the list

int get_element() { return cursor->data;}

void advance() { cursor = cursor->next; }

void print();

private:

list_element *head;

list_element *cursor;

};

// constructor : move elements from an array

list::list(const int array[], int sz)

{

head = cursor = 0;

// populate the list element using add()

for(int i = 0; i < sz; ++i) {

add(array[i]);

}

}

// destructor

list::~list()

{

for(cursor = head; cursor != 0;) {

cursor = head->next;

delete head;

head = cursor;

}

}

void list::prepend(int n)

{

// swap head with current head

if(head) {

head = cursor = new list_element(n, head);

}

// if empty list, make current element as head

else

head = new list_element(n, head);

}

void list::add(int n)

{

if(head) {

cursor = head;

while(cursor) {

// end of the list

if(cursor->next == NULL) {

cursor->next = new list_element(n);

break;

}

// advance to the next element

else

advance();

}

}

// no head, make head with current element

else {

head = new list_element(n);

}

}

void list::print()

{

if(head)

{

cursor = head;

while(cursor) {

cout << get_element() << " ";

advance();

}

}

else

cout << "Empty list!";

cout << endl;

}

int main()

{

int arr[] = {1, 2, 3, 4, 5};

list myList(arr,5);

myList.add(6);

myList.prepend(0);

myList.print();

list a, b;

cout << "first print\n";

a.print();

a.prepend(9); a.prepend(8);

cout << "list a" << endl;

a.print();

for (int i = 0; i < 40; i++)

b.prepend(i*i);

cout << "lisb b" << endl;

b.print();

return 0;

}