أرسل هذا في رسالة قصيرة: The complexity of cyber attacks in a new layered-security model and the maximum-weight, rooted-subtree problem

  ______    ______   _____     _    _     ______  
 /_   _//  /_   _// |  __ \\  | || | ||  /_   _// 
   | ||     -| ||-  | |  \ || | || | ||  `-| |,-  
  _| ||     _| ||_  | |__/ || | \\_/ ||    | ||   
 /__//     /_____// |_____//   \____//     |_||   
 `--`      `-----`   -----`     `---`      `-`'