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

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發送短信 : Reflecting triangles with a dense set of vertex points in the plane