發送短信 : Invariance and efficiency of convex representations

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