發送短信

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

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發送短信 : A unified method of teaching conic sections