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@theodesp
Created June 8, 2014 19:54
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List Data Structure
function List() {
this.listSize = 0;
this.pos = 0;
this.dataStore = []; // initializes an empty array to store list elements
this.clear = clear;
this.find = find;
this.toString = toString;
this.insert = insert;
this.append = append;
this.remove = remove;
this.start = start;
this.end = end;
this.prev = prev;
this.next = next;
this.length = length;
this.currPos = currPos;
this.at = at;
this.getElement = getElement;
this.length = length;
this.contains = contains;
}
// Push to the end
function push(element) {
this.dataStore[this.listSize++] = element; // O(1)
}
// Find element in array
function find(element) {
for (var i = 0; i < this.dataStore.length; ++i) { // O(n)
if (this.dataStore[i] == element) {
return i;
}
}
return -1;
}
// Remove element if exists
function remove(element) {
var foundAt = this.find(element); // O(n)
if (foundAt > -1) {
this.dataStore.splice(foundAt, 1); // O(n)
--this.listSize;
return true;
}
return false;
}
// Get length
function length() {
return this.listSize; // O(1)
}
// Print the array
function toString() {
return this.dataStore; // O(n)
}
// Insert the element after
function insert(element, after) {
var insertPos = this.find(after); // O(n)
if (insertPos > -1) {
this.dataStore.splice(insertPos + 1, 0, element); // O(n)
++this.listSize;
return true;
}
return false;
}
// Zero the list
function clear() { // O(1)
delete this.dataStore;
this.dataStore = [];
this.listSize = this.pos = 0;
}
// Check if element exists in the list
function contains(element) {
for (var i = 0; i < this.dataStore.length; ++i) { // O(n)
if (this.dataStore[i] == element) {
return true;
}
}
return false;
}
// First
function start() {
this.pos = 0; // O(1)
}
// last
function end() {
this.pos = this.listSize - 1; // O(1)
}
// Previus
function prev() {
if (this.pos > 0) { // O(1)
--this.pos;
}
}
// Next
function next() {
if (this.pos < this.listSize - 1) { // O(1)
++this.pos;
}
}
// Current
function currPos() {
return this.pos; // O(1)
}
// Go at position
function at(position) {
this.pos = position; // O(1)
}
// Get current element
function getElement() {
return this.dataStore[this.pos]; // O(1)
}
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