Javascript Algorithm String Palindrome

function Stack() {
  this.dataStore = [];//from  ww w  .ja v  a2  s .co  m
  this.top = 0;
  this.push = push;
  this.pop = pop;
  this.peek = peek;
  this.clear = clear;
  this.length = length;
}

function push(element) {
  this.dataStore[this.top++] = element;
}

function peek() {
  return this.dataStore[this.top - 1];
}

function pop() {
  return this.dataStore[--this.top];
}

function clear() {
  this.top = 0;
}

function length() {
  return this.top;
}

function isPalindrome(word) {
  let s = new Stack();
  for (let i = 0; i < word.length; ++i) {
    s.push(word[i]);
  }
  let rword = "";
  while (s.length() > 0) {
    rword += s.pop();
  }
  if (word == rword) {
    return true;
  } else {
    return false;
  }
}

let word = "hello";
if (isPalindrome(word)) {
  console.log(word + " is a palindrome.");
} else {
  console.log(word + " is not a palindrome.");
}
word = "racecar"
if (isPalindrome(word)) {
  console.log(word + " is a palindrome.");
} else {
  console.log(word + " is not a palindrome.");
}