http://cs1.utm.edu/icpc/ 2026-05-03T00:34:34+00:00 http://cs1.utm.edu/icpc/ http://cs1.utm.edu/icpc/lib/tpl/dokuwiki/images/favicon.ico text/html 2019-05-07T16:48:03+00:00 jguerin (jguerin@undisclosed.example.com) http://cs1.utm.edu/icpc/doku.php?id=python3:priority_queue&rev=1557265683&do=diff Python3 Priority Queues Insertion & Removal import queue q = queue.PriorityQueue() q.put(10) q.put(1) q.put(5) while not q.empty(): print(q.get()) # 1 5 10 Modifying Priority Unlike C++ and Java, the standard priority queue in Python3 does not take a comparator on declaration. There are two means of dealing with a modified priority or a priority that is separate from the object: text/html 2019-05-07T16:19:12+00:00 jguerin (jguerin@undisclosed.example.com) http://cs1.utm.edu/icpc/doku.php?id=python3:list_comprehensions&rev=1557263952&do=diff List Comprehensions List comprehensions are used for creating lists from existing lists and other iterable structures. List comprehensions typically follow formatting similar to set-builder notation in discrete mathematics. Syntax Consider the following illustrative Python3 example for generating a list of squares: text/html 2019-05-07T14:52:00+00:00 jguerin (jguerin@undisclosed.example.com) http://cs1.utm.edu/icpc/doku.php?id=python3&rev=1557258720&do=diff 1. Python Language Reference Programming languages are a tool. While many modern programming languages are designed to be general purpose, some programming languages may be better suited to solve certain problems than others. When to use Python3 While efficiency of a text/html 2019-05-07T13:10:46+00:00 jguerin (jguerin@undisclosed.example.com) http://cs1.utm.edu/icpc/doku.php?id=python3:recursion_depth&rev=1557252646&do=diff Recursion Depth Limits Factorial The factorial function is a canonical recursive example. Factorial has a convenient recursive definition as n! = n * (n -- 1)! where 0! = 1! = 1. The following is a standard implementation derived from this definition: def factorial(n): if n == 0: return 1 else: return n * factorial(n-1) print(factorial(997)) text/html 2019-05-07T12:43:14+00:00 jguerin (jguerin@undisclosed.example.com) http://cs1.utm.edu/icpc/doku.php?id=python3:lru_cache&rev=1557250994&do=diff LRU Cache Memoization is a common optimization technique where repeatedly computed values are cached for quick lookup. While memoization can be achieved by a relatively simple modification to many recursive formulations, Python3's functools library implements automatic memoization in the form of an LRU (least recently used) cache as a