發送短信

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__    __   __   __    _  _     ______   ______   
\ \\ / //  \ \\/ //  | \| ||  /_   _// |      \\ 
 \ \/ //    \ ` //   |  ' ||   -| ||-  |  --  // 
  \  //      | ||    | .  ||   _| ||_  |  --  \\ 
   \//       |_||    |_|\_||  /_____// |______// 
    `        `-`'    `-` -`   `-----`  `------`

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發送短信 : An efficient and practical scheme for privacy protection in e-commerce of digital goods