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Does python provide functions for performing binary search on sorted lists, analogous to the std::lower_bound and std::upper_bound algorithms of the C++ Standard Library?

Leon
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2 Answers2

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Those functions are located in the bisect module:

  • bisect.bisect_left(a, x, lo=0, hi=len(a)) is the analog of std::lower_bound().

  • bisect.bisect_right(a, x, lo=0, hi=len(a)) is the analog of std::upper_bound().

Note: there is also a function bisect() which is an alias for bisect_right().

Leon
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There is also sortedcontainers package in python, which also has bisect_left and bisect_right. https://grantjenks.com/docs/sortedcontainers/sortedlist.html

This could be handy if you don't want to maintain the list sorted yourself (e.g. insertion).

Mircea
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