title: Gets an error multiplying Swift Ints
body: <p>New Swift enthusiast here! I'm following Rey Wenderlich's <a href="http://www.raywenderlich.com/75270/make-game-like-candy-crush-with-swift-tutorial-part-1" rel="nofollow">Candy Crush tutorial</a> and get an error when multiplying two <code>Int</code> values. I know Swift is strictly typed so would be the reason? Am I not allowed to do this in Swift? Note the <code>error</code> comments where I'm having trouble. Any help in the right direction is greatly appreciated!</p>
  
  <pre><code>class Array2D&lt;T&gt; {
    let columns: Int
    let rows: Int
    let array: Array&lt;T&gt;
  
    init(columns: Int, rows: Int) {
      self.columns = columns
      self.rows = rows
      array = Array&lt;T?&gt;(count: rows*columns, repeatedValue: nil)    // ERROR: could not find an overload for '*' that accepts the supplied arguments
    }
  
    subscript(column: Int, row: Int) -&gt; T? {
      get {
          return array[row*columns + column]
      }
      set {
          array[row*columns + column] = newValue   // ERROR: could not find an overload for '*' that accepts the supplied arguments
      }
    }
  }
  </code></pre>