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

Please enter what you see:

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