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  ______   _    _     ____       ___      ____    
 /_   _// | || | ||  |  _ \\    / _ \\   |  _ \\  
 `-| |,-  | || | ||  | |_| ||  | / \ ||  | |_| || 
   | ||   | \\_/ ||  | .  //   | \_/ ||  | .  //  
   |_||    \____//   |_|\_\\    \___//   |_|\_\\  
   `-`'     `---`    `-` --`    `---`    `-` --`

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發送短信 : Automatic and polynomial-time algebraic structures