Hashing

Hash consing

In computer science, particularly in functional programming, hash consing is a technique used to share values that are structurally equal. The term hash consing originates from implementations of Lisp that attempt to reuse cons cells that have been constructed before, avoiding the penalty of memory allocation. Hash consing is most commonly implemented with hash tables storing weak references that may be garbage-collected when the data stored therein contains no references from outside the table. Hash consing has been shown to give dramatic performance improvements—both space and time—for symbolic and dynamic programming algorithms. An interesting property of hash consing is that two structures can be tested for equality in constant time, which in turn can improve efficiency of divide and conquer algorithms when data sets contain overlapping blocks. (Wikipedia).

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Cryptography (part 3 of 3)

An informal introduction to cryptography. Part of a larger series teaching programming at http://codeschool.org

From playlist Cryptography

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Java Hash Table

Get the Code Here: http://goo.gl/srwIf Welcome to my Java Hash Table tutorial. A Hash Table is a data structure offers fast insertion and searching capabilities. The negative is that they are limited in size because they are based on arrays. They are also hard to order. People get confus

From playlist Java Algorithms

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Lecture 5B | MIT 6.001 Structure and Interpretation, 1986

Computational Objects Despite the copyright notice on the screen, this course is now offered under a Creative Commons license: BY-NC-SA. Details at http://ocw.mit.edu/terms Subtitles for this course are provided through the generous assistance of Henry Baker, Hoofar Pourzand, Heather

From playlist MIT 6.001 Structure and Interpretation, 1986

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RubyConf 2016 - Seeing Metaprogramming and Lambda Function Patterns in Ruby by Lukas Nimmo

RubyConf 2016 - Seeing Metaprogramming and Lambda Function Patterns in Ruby by Lukas Nimmo Metaprogramming and lambda functions in Ruby should be explained within their rightful place: living examples. You may have read tutorials on what these concepts are, but still do not understand whe

From playlist RubyConf 2016

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Android Open 2011: Kelly Goto, "Content & Connection: New Approaches to Mobile Ethnography"

Android Open 2011: Kelly Goto, "Content & Connection: New Approaches to Mobile Ethnography"

From playlist Android Open 2011

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What Is Hashing? | What Is Hashing With Example | Hashing Explained Simply | Simplilearn

🔥Advanced Executive Program In Cybersecurity: https://www.simplilearn.com/pgp-advanced-executive-program-in-cyber-security?utm_campaign=WhatIsHashing&utm_medium=Descriptionff&utm_source=youtube 🔥Caltech Cybersecurity Bootcamp(US Only): https://www.simplilearn.com/cybersecurity-bootcamp?utm

From playlist Cyber Security Playlist [2023 Updated]🔥

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Clojure Conj 2012 - Web Testing with Logic Programming

Web Testing with Logic Programming by: Daniel Gregoire There are a plethora of libraries and frameworks for authoring tests at all levels, but how do we test complex application states? Higher-level tests that need to verify complex scenarios tend to result in sequential, nested condition

From playlist Clojure Conf 2012

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Hash Tables and Hash Functions

This computer science video describes the fundamental principles of the hash table data structure which allows for very fast insertion and retrieval of data. It covers commonly used hash algorithms for numeric and alphanumeric keys and summarises the objectives of a good hash function. Co

From playlist Data Structures

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Hash function by analogy

https://en.wikipedia.org/wiki/SHA-1#Examples_and_pseudocode If you have any questions of want to contribute to code or videos, feel free to write me a message on youtube or get my contact in the About section or googling my contacts.

From playlist Programming

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What is a Hashtag?

In this video, you’ll learn more about how hashtags are used on Twitter. Visit https://www.gcflearnfree.org/twitter/what-is-a-hashtag/1/ for our text-based lesson. This video includes information on: • Using hashtags • Browsing popular hashtags We hope you enjoy!

From playlist Twitter

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Lecture 10B | MIT 6.001 Structure and Interpretation, 1986

Storage Allocation and Garbage Collection Despite the copyright notice on the screen, this course is now offered under a Creative Commons license: BY-NC-SA. Details at http://ocw.mit.edu/terms Subtitles for this course are provided through the generous assistance of Henry Baker, Hoof

From playlist MIT 6.001 Structure and Interpretation, 1986

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Lecture 10B: Storage Allocation and Garbage Collection

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From playlist MIT 6.001 Structure and Interpretation, 1986

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Lecture 5B: Computational Objects

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From playlist MIT 6.001 Structure and Interpretation, 1986

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Lecture 3A | MIT 6.001 Structure and Interpretation, 1986

Henderson Escher Example Despite the copyright notice on the screen, this course is now offered under a Creative Commons license: BY-NC-SA. Details at http://ocw.mit.edu/terms Subtitles for this course are provided through the generous assistance of Henry Baker, Hoofar Pourzand, Heather W

From playlist MIT 6.001 Structure and Interpretation, 1986

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Collide Geneva - Final presentation by artist Cassandre Poirier-Simon

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From playlist Arts@CERN

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Gromov–Witten Invariants and the Virasoro Conjecture (Remote Talk) by Ezra Getzler

J-Holomorphic Curves and Gromov-Witten Invariants DATE:25 December 2017 to 04 January 2018 VENUE:Madhava Lecture Hall, ICTS, Bangalore Holomorphic curves are a central object of study in complex algebraic geometry. Such curves are meaningful even when the target has an almost complex stru

From playlist J-Holomorphic Curves and Gromov-Witten Invariants

Related pages

Communications of the ACM | Cons | Interning (computer science) | Garbage collection (computer science) | String interning | Dynamic programming | Reference (computer science) | Hashlife | Weak reference | Merkle tree | Hash table