gribnoysup

function Node (val) {
  this.val = val;
  this.next = null;
}

function LinkedList (firstVal) {
  this.__head = null;
  this.__length = 0;
  if (typeof firstVal !== 'undefined') {
    this.append(firstVal);

gribnoysup

function StaticQueue (size) {
  this.__arr = {};
  this.__size = size;
  this.__front = -1;
  this.__rear = -1;
  
  for (var i = 0; i < size; i++) {
    this.__arr[i] = undefined;
  }
}

gribnoysup

function Stack () {
  this.__arr = [];
}

Stack.prototype = {
  constructor : Stack,
  push : function push (elem) {
    if (typeof elem !== 'undefined') return this.__arr.push(elem);
  },
  pop : function pop () {

gribnoysup

function infixToPostfixWithParentheses (expr) {
  if (!balancedParentheses(expr)) return false;
  
  var postfix = '', i = 0, len = 0;
  var stack = new Stack();

  for (i, len = expr.length; i < len; i++) {
    if (expr[i].match(/[^\(\)\+\-\*\/\%]/)) {
      postfix += expr[i];
    } else if (stack.isEmpty()) {

gribnoysup

function infixToPostfixNoParentheses (expr) {
  var postfix = '', i = 0, len = 0;
  var stack = new Stack();
  
  for (i, len = expr.length; i < len; i++) {
    if (expr[i].match(/[^\+\-\*\/\%]/)) {
      postfix += expr[i];
    } else if (stack.isEmpty()) {
      stack.push(expr[i]);
    } else {

gribnoysup

function evalPostfix (expr) {
  var i = 0, len = 0, op1, op2;
  var stack = new Stack();
  
  for (i = 0, len = expr.length; i < len; i++) {
    if (expr[i].match(/[^\+\-\*\/\%]/)) {
      stack.push(expr[i]);
    } else {
      op2 = stack.pop();
      op1 = stack.pop();

gribnoysup

function balancedParentheses (string) {
  var stack = new Stack();
  var i, len;
  
  string = string
    // remove any strings or regexes used in target string (if it is a function for example)
    .replace(/(\`.{0,}\`|\/.{0,}\/|\'.{0,}\'|\".{0,}\")/g, '');
  
  for (i = 0, len = string.length; i < len; i++) {
    switch (string[i]) {