發送短信 : Identifying correlated heavy-hitters

 _____     _    _     ____       ___     __   __  
|  __ \\  | || | ||  |  _ \\    / _ \\   \ \\/ // 
| |  \ || | || | ||  | |_| ||  | / \ ||   \   //  
| |__/ || | \\_/ ||  | .  //   | \_/ ||   / . \\  
|_____//   \____//   |_|\_\\    \___//   /_//\_\\ 
 -----`     `---`    `-` --`    `---`    `-`  --`