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# Counting Circles Without Computing Them

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LIPIcs.FUN.2016.17.pdf
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## Cite As

Rudolf Fleischer. Counting Circles Without Computing Them. In 8th International Conference on Fun with Algorithms (FUN 2016). Leibniz International Proceedings in Informatics (LIPIcs), Volume 49, pp. 17:1-17:7, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2016)
https://doi.org/10.4230/LIPIcs.FUN.2016.17

## Abstract

In this paper we engineer a fast algorithm to count the number of triangles defined by three lines out of a set of n lines whose circumcircle contains the origin. The trick is not to compute any triangles or circles.
##### Keywords
• lines arrangement
• triangle
• circumcircle
• inscribed angle theorem

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## References

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