1. L1
    1. L1.1
    2. L1.2
  2. L2
    1. L2.1
    2. L2.2
    3. L2.3
  3. L3
    1. L3.1
    2. L3.2
    3. L3.3
    4. L3.4
      1. L3.4.1
      2. L3.4.2
  1. R1
    1. R1.1
    2. R1.2
    3. R1.3
      1. R1.3.1
      2. R1.3.2
        1. R1.3.2.1
      3. R1.3.3
  2. R2
    1. R2.1
    2. R2.2
    3. R2.3
    4. R2.4
  3. R3
    1. R3.1
    2. R3.2
    3. R3.3
⟰

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