發送短信

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           __   __   _    _     _____    __   __  
  ____     \ \\/ // | || | ||  |  ___||  \ \\/ // 
 |    \\    \ ` //  | || | ||  | ||__     \   //  
 | [] ||     | ||   | \\_/ ||  | ||__     / . \\  
 |  __//     |_||    \____//   |_____||  /_//\_\\ 
 |_|`-`      `-`'     `---`    `-----`   `-`  --` 
 `-`

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發送短信 : Inefficiency in the Shadow of Unobservable Outside Options