   }
   
   override func main() {
-    for pair in inputArray {
-      if cancelled { return }
-      outputArray.append(slowAdd(pair))
-    }
+    // TODO: fill in this
   }
 }
 

let numberArray = [(1,2), (3,4), (5,6), (7,8), (9,10)]

//: Operation and queue
let sumOperation = AnotherArraySumOperation(input: numberArray)
let queue = NSOperationQueue()

//: Start the operation and
startClock()
queue.addOperation(sumOperation)

sumOperation.cancel()

queue.waitUntilAllOperationsAreFinished()
stopClock()

  }
  
  override func main() {
    // TODO: Fill in this
  }
}

