發送短信

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

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發送短信 : Testing for Indirect Reciprocity in Charitable Activities