 let numberArray = [(1,2), (3,4), (5,6), (7,8), (9,10)]
 
 //: Operation and queue
-let sumOperation = AnotherArraySumOperation(input: numberArray)
+let sumOperation = ArraySumOperation(input: numberArray)
 let queue = NSOperationQueue()
 
 //: Start the operation and
 startClock()
 queue.addOperation(sumOperation)
 
-sumOperation.cancel()
+
 
 queue.waitUntilAllOperationsAreFinished()
 stopClock()

  }
  
  override func main() {
    outputArray = slowAddArray(inputArray) {
      progress in
      print("\(progress*100)% of the array processed.")
      return !self.cancelled
    }
  }
}


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

