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Need
the following operations:
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Insert
segment
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Delete
segment
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Tell me
the two segments
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adjacent
to this one (along
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the
sweepline)
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Swap
two segments along
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the
sweepline (needed when
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an
intersection occurs)
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We
can use a balanced tree!
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Runtime
analysis
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– |
The
loop is executed O(n+k)
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times
where k is the number
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of
intersections
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– |
Each
PQ operations within
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the
loop takes time O(log n)
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(using
a heap)
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– |
The
operations needed to
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maintain
adjacency
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information
each take time
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O(log
n) (using a balanced
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tree)
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Total
time: O((n+k)log n)
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