發送短信

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

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發送短信 : A Visualization App on Proving Geometric Concepts