95 lines
4.0 KiB
Markdown
95 lines
4.0 KiB
Markdown
---
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title: Open Addressing
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TARGET DECK: Obsidian::STEM
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FILE TAGS: hashing::open
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tags:
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- hashing
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---
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## Overview
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In **open addressing**, keys always reside in the hash table. Collisions are dealt with by searching for other empty buckets within the hash table.
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%%ANKI
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Basic
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What does "closed" refer to in term "closed hashing"?
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Back: A key must reside in the hash table.
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Reference: “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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<!--ID: 1718198717434-->
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END%%
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%%ANKI
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Basic
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What does "open" refer to in term "open addressing"?
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Back: A key is not necessarily stored in the slot it hashes to.
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Reference: “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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<!--ID: 1718198717447-->
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END%%
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%%ANKI
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Cloze
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{Open} addressing is also known as {closed} hashing.
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Reference: “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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<!--ID: 1718198717455-->
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END%%
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%%ANKI
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Cloze
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The following is an example of {closed} hashing.
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![[open-addressing.png]]
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Reference: “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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<!--ID: 1718198717464-->
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END%%
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%%ANKI
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Cloze
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The following is an example of {open} addressing.
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![[open-addressing.png]]
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Reference: “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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<!--ID: 1718198755486-->
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END%%
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%%ANKI
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Basic
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What is the theoretical maximum load factor in open addressing?
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Back: $1$
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Reference: “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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<!--ID: 1718759188171-->
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END%%
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%%ANKI
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Basic
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*Why* is the theoretical maximum load factor of open addressing unbounded?
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Back: An open addressing hash table can only store as many entries as slots.
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Reference: “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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<!--ID: 1718759188176-->
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END%%
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%%ANKI
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Basic
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When is the load factor of an open addressing hash table $0$?
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Back: When no entries are stored in the table.
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Reference: Thomas H. Cormen et al., Introduction to Algorithms, Fourth edition (Cambridge, Massachusett: The MIT Press, 2022).
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<!--ID: 1718759188179-->
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END%%
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%%ANKI
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Basic
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When is the load factor of a open addressing hash table $1$?
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Back: When there exist the same number of total entries as slots.
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Reference: Thomas H. Cormen et al., Introduction to Algorithms, Fourth edition (Cambridge, Massachusett: The MIT Press, 2022).
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<!--ID: 1718759188182-->
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END%%
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%%ANKI
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Basic
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When is the load factor of an open addressing hash table $> 1$?
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Back: N/A
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Reference: Thomas H. Cormen et al., Introduction to Algorithms, Fourth edition (Cambridge, Massachusett: The MIT Press, 2022).
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<!--ID: 1718759188186-->
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END%%
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## Bibliography
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* “Hash Tables: Open vs Closed Addressing | Programming.Guide,” accessed June 12, 2024, [https://programming.guide/hash-tables-open-vs-closed-addressing.html](https://programming.guide/hash-tables-open-vs-closed-addressing.html).
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* Thomas H. Cormen et al., Introduction to Algorithms, Fourth edition (Cambridge, Massachusett: The MIT Press, 2022). |