1. 1.
    0
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    ···
  2. 2.
    0
    ahahaha
    ···
  3. 3.
    0
    ahahaha
    ···
  4. 4.
    0
    ahahahah
    ···
  5. 5.
    0
                                                     ▲                              ∆
                                                   ▲ ▲                           ∆ ∆
    ···