01234
123  abc

          *
        *  *
      *  *  *
    *  *  *  *
  *  *  *  *  *
    *  *  *  *
      *  *  *
        *  *
          *

          1
        2  2
      3  3  3
    4  4  4  4
  5  5  5  5  5
    4  4  4  4
      3  3  3
        2  2
          1

          4
        3  3
      2  2  2
    1  1  1  1
  0  0  0  0  0
    1  1  1  1
      2  2  2
        3  3
          4

          1
        1  2
      1  2  3
    1  2  3  4
  1  2  3  4  5
    1  2  3  4
      1  2  3
        1  2
          1

12345
1234
123
12
1

1
12
123
1234
12345

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* *
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