Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/fuston05/cs-module-project-hash-tables_2
copy of lambda school repo for extra practice: python hash tables
https://github.com/fuston05/cs-module-project-hash-tables_2
data-structures hashtable python3
Last synced: 5 days ago
JSON representation
copy of lambda school repo for extra practice: python hash tables
- Host: GitHub
- URL: https://github.com/fuston05/cs-module-project-hash-tables_2
- Owner: fuston05
- Created: 2020-07-28T11:40:24.000Z (over 4 years ago)
- Default Branch: master
- Last Pushed: 2020-07-29T18:55:35.000Z (over 4 years ago)
- Last Synced: 2024-11-12T06:31:38.513Z (2 months ago)
- Topics: data-structures, hashtable, python3
- Language: Python
- Homepage:
- Size: 35.2 KB
- Stars: 1
- Watchers: 3
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# Hash Tables
## Day 1
Task: Implement a basic hash table without collision resolution.
1. Implement a `HashTable` class and `HashTableEntry` class.
2. Implement a good hashing function.
Recommend either of:
* DJB2
* FNV-1 (64-bit)
You are allowed to Google for these hashing functions and implement
from psuedocode.
3. Implement the `hash_index()` that returns an index value for a key.
4. Implement the `put()`, `get()`, and `delete()` methods.
You can test this with:
```
python test_hashtable_no_collisions.py
```
The above test program is _unlikely_ to have collisions, but it's
certainly possible for various hashing functions. With DJB2 (32 bit) and
FNV-1 (64 bit) hashing functions, there are no collisions.
## Day 2
Task: Implement linked-list chaining for collision resolution.
1. Modify `put()`, `get()`, and `delete()` methods to handle collisions.
2. There is no step 2.
You can test this with:
```
python test_hashtable.py
```
Task: Implement load factor measurements and automatic hashtable size
doubling.
1. Compute and maintain load factor.
2. When load factor increases above `0.7`, automatically rehash the
table to double its previous size.
Add the `resize()` method.
You can test this with both of:
```
python test_hashtable.py
python test_hashtable_resize.py
```
Stretch: When load factor decreases below `0.2`, automatically rehash
the table to half its previous size, down to a minimum of 8 slots.
## Day 3 and Day 4
Work on the hashtable applications directory (in any order you
wish--generally arranged from easier to harder, below).
For these, you can use either the built-in `dict` type, or the hashtable
you built. (Some of these are easier with `dict` since it's more
full-featured.)
* [Lookup Table](applications/lookup_table/)
* [Expensive Sequence](applications/expensive_seq/)
* [Word Count](applications/word_count/)
* [No Duplicates](applications/no_dups/)
* [Markov Chains](applications/markov/)
* [Histogram](applications/histo/)
* [Cracking Caesar Ciphers](applications/crack_caesar/)
* [Sum and Difference](applications/sumdiff/)