SOURCE

function divideByBase(number, base) {
  var remStack = [];
  var digits = '0123456789ABCDEF';
  var result = '';
  while (number > 0) {
    rem = number % base;
    remStack.unshift(rem);
    number = number / base >> 0;
  }
  for (var i = 0; i < remStack.length; i++) {
    result += digits[remStack[i]];
  }
  return result;
}

// console.log(divideByBase(200, 16))
function Node(number) {
  this.next = null;
  this.element = number;
}

function LinkedList() {
  this.head = null;
  this.length = 0;
}

LinkedList.prototype = {
  constructor: LinkedList,
  getHead: function() {
    return this.head;
  },
  append: function(number) {
    var node = new Node(number);
    var currentNode;
    if (this.head === null) {
      this.head = node;
    } else {
      currentNode = this.head;
      while (currentNode.next) {
        currentNode = currentNode.next;
      }
      currentNode.next = node;
    }
    this.length++;
  },
  insert: function(pos, number) {
    if (pos >= 0 && pos <= this.length) {
      var node = new Node(number);
      var currentNode = this.head;
      var previousNode;
      var index = 0;
      if (pos === 0) {
      	node.next = this.head;
        this.head = node;
      } else {
        while (index++ < pos) {
          previousNode = currentNode;
          currentNode = currentNode.next;
        }
        node.next = currentNode;
        previousNode.next = node;
      }
      this.length++;
      return true;
    } else {
      return false;
    }
  },
  removeAt(pos) {
    if (pos > -1 && pos < this.length) {
      var currentNode = this.head;
      var previousNode;
      var index = 0;
      if (pos === 0) {
        this.head = currentNode.next;
      } else {
        while (index++ < pos) {
          previousNode = currentNode;
          currentNode = currentNode.next;
        }
        previousNode.next = currentNode.next;
      }
      this.length--;
    } else {
      return false;
    }
  }
};


var a = new LinkedList();
// a.append(3);
// a.insert(0, 5);
// a.insert(1, 4);

// console.log(a);
// a.removeAt(2);
// console.log(a);