33 lines
1 KiB
Markdown
33 lines
1 KiB
Markdown
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## Problem statement
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This solves the following problem:
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```
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Given a set of rectilinear rectangles in the plane, each by coordinates of opposing corners,
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calculate the area of their union.
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```
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It was a task to show that this is solvable in `O(n^2)` on one of my exercise sheets.
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Because I had some spare time, I decided to implement this.
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Actually, this can be done in `O(nlog n)` time using a sweepline algorithm
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that makes use of [segment trees][st].
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The implementation tries to be reasonably fast and respects `nlog n` running time,
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but is certainly not too optimized and more of a showcase.
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## Build
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A standard `C++` installation along with `CMake` should to the job.
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Remove the benchmark targets if you do not need them.
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## Benchmark
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Just for fun, I played around with the [Google Benchmark Library][gl-benchmark].
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You will have to install the library and statically link to it to run the
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benchmarks.
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See the github page of the benchmark library for details.
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[gl-benchmark]: https://github.com/google/benchmark
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[st]: https://en.wikipedia.org/wiki/Segment_tree
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