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   _____     ___                _____      _____  
  / ___//   / _ \\      ___    |  ___||   / ___// 
  \___ \\  / //\ \\    /   ||  | ||__     \___ \\ 
  /    // |  ___  ||  | [] ||  | ||__     /    // 
 /____//  |_||  |_||   \__ ||  |_____||  /____//  
`-----`   `-`   `-`     -|_||  `-----`  `-----`   
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發送短信 : Combinatorial Algebraic Topology