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Miklós Schweitzer
2020 Miklós Schweitzer
4
4
Part of
2020 Miklós Schweitzer
Problems
(1)
horizontal and vertical segments intersected by curves
Source: Miklos Schweitzer 2020, Problem 4
12/1/2020
Consider horizontal and vertical segments in the plane that may intersect each other. Let
n
n
n
denote their total number. Suppose that we have
m
m
m
curves starting from the origin that are pairwise disjoint except for their endpoints. Assume that each curve intersects exactly two of the segments, a different pair for each curve. Prove that
m
=
O
(
n
)
m=O(n)
m
=
O
(
n
)
.
geometry
combinatorics