title: Adding Element to End of Vector
body: <p><a href="http://www.scala-lang.org/api/current/index.html#scala.collection.immutable.Vector">Scaladocs</a> explain how to add an element to a Vector.</p>
  
  <pre><code>def :+(elem: A): Vector[A]
  [use case] A copy of this vector with an element appended.
  </code></pre>
  
  <p>Example:</p>
  
  <pre><code>scala&gt; Vector(1,2) :+ 3
  res12: scala.collection.immutable.Vector[Int] = Vector(1, 2, 3)
  </code></pre>
  
  <p>For a large collection, it seems expensive to copy the whole Vector, and then add an element to it.</p>
  
  <p>What's the best(fastest) way to add an element to a Vector?</p>