linkedList.cpp

Code

/*
    linkedList.cpp
    CIS 250
    David Klick
    2010-03-15

    Linked list specification
*/

#include "linkedList.h"
#include <iostream>
#include <string>
#include <assert.h>
using std::cout;
using std::endl;
using std::string;

linkedList::linkedList() {
    count = 0;
    head = NULL;
}

linkedList::~linkedList() {
    while (head != NULL) {
          node* hold = head->next;
          delete head;
          head = hold;
          count--;
    }
}

int linkedList::length() const {
    return count;
}

void linkedList::print() const {
    node* pos = head;
    while (pos != NULL) {
        cout << pos->data << " ";
        pos = pos->next;
    }
    cout << endl;
}

bool linkedList::search(int val) const {
    bool found = false;
    node* pos = head;
    while (pos != NULL) {
        if (pos->data == val) {
            found = true;
            break;
        }
        pos = pos->next;
    }
    return found;
}

int linkedList::front() const {
    if (head == NULL) throw string("Error: Accessing empty list");
    return head->data;
}

int linkedList::back() const {
    if (head == NULL) throw string("Error: Accessing empty list");
    node* pos = head;
    while (pos->next != NULL) pos = pos->next;
    return pos->data;
}

bool linkedList::isEmpty() const {
    return head == NULL;
}

void linkedList::addFirst(int val) {
    node* newNode = new node;
    assert (newNode != NULL);
    newNode>data = val;
    newNode>next = head;
    head = newNode;
    count++;
}

void linkedList::addLast(int val) {
    node* newNode = new node;
    assert (newNode != NULL);
    newNode>data = val;
    newNode>next = NULL;
    if (head == NULL) {
        head = newNode;
    } else {
        node* pos = head;
        while (pos->next != NULL) pos = pos->next;
        pos->next = newNode;
    }
    count++;
}

void linkedList::add(int val) {
    addLast(val);
}

bool linkedList::remove(int val) {
    if (head == NULL) return false;
    if (head->data == val) {
        node *temp = head;
        head = head->next;
        delete temp;
        count--;
        return true;
    }
    node* prev = head;
    node* curr = prev->next;
    while (curr != NULL) {
        if (curr->data == val) {
            prev->next = curr->next;
            delete curr;
            count--;
            return true;
        } else {
            prev = curr;
            curr = curr->next;
        }
    }
    return false;
}

ostream& operator<<(ostream& out, const linkedList &lst) {
    linkedList::node* current = lst.head;
    while (current != NULL) {
        out << current->data << " ";
        current = current->next;
    }
    return out;
}