In the last tutorial, the main lesson was that list-based code can look fine and still lead to slow contest solutions. This tutorial is about the tool that often fixes that mistake. and seen is a list ...

Sets in Python organize collections of unique objects. Learn how to take advantage of this powerful feature in your own code. Of the major data types built into Python, the set is one of the least ...

On the tutorial's "Data Structures" page, each section visibly links to the relevant part of the "Built-in Types" page for more comprehensive information, except the Sets section does not and could ...