https://github.com/shoyamanishi/redblacktree

A faithful implementation of the red black tree algorithm by Cormen, Leiserson, Rivest, and Stein.
https://github.com/shoyamanishi/redblacktree

algorithm python3 redblack-tree

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A faithful implementation of the red black tree algorithm by Cormen, Leiserson, Rivest, and Stein.

• Host: GitHub
• URL: https://github.com/shoyamanishi/redblacktree
• Owner: ShoYamanishi
• License: mit
• Created: 2020-09-03T19:49:48.000Z (over 4 years ago)
• Default Branch: master
• Last Pushed: 2020-09-06T16:00:55.000Z (over 4 years ago)
• Last Synced: 2023-08-12T07:02:35.749Z (over 1 year ago)
• Topics: algorithm, python3, redblack-tree
• Language: Python
• Homepage:
• Size: 270 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# CLRS Red-Black-Tree Algorithm in Python

 

A python implementation of the Red-black-tree algorithm by Cormen, Leiserson, Rivest, and Stein [CLRS]

I find the description by [CLRS] the most accurate, concise, and easiest to understand.

The only two changes I made are the extra checks for NIL parameter in the beginning of LEFT_ and RIGHT_ROTATE().

# Dependencies

* **Graphviz** for drawing trees. Comment out import if you don't need to draw.

# Usage

See Chap. 13 & 14 in [CLRS]

* **Create a Tree** ```t = rbtree.RedBlackTree()```

* **Create a Node** ```n = rbtree.RedBlackNode(0.0)```

* **Insert a node to a tree** ```t.RB_INSERT(n)```

* **Remove a node from a tree** ```t.RB_DELETE(n)```

* **Root node** n = ```n = t.ROOT()```

* **Minimum node** n = ```n = t.TREE_MINIMUM(t.ROOT())```

* **Maximum node** n = ```n =  t.TREE_MAXIMUM(t.ROOT())```

* **Iterate ascending**

```python

for v in t:

    print(v)

```

or

```python

n = t.TREE_MINIMUM(t.ROOT())

while not n is t.NIL():

    n = t.TREE_SUCCESSOR(n)

    print(n)

```

* **Iterate descending**

```python

n = t.TREE_MAXIMUM(t.ROOT())

while not n is t.NIL():

    n = t.TREE_PREDECESSOR(n)

    print(n)

```

* **draw tree** ```t.draw('filename_wo_ext', True, 'pdf', 'vertical' )```

See [unit_tests_rbtree.py](unit_tests_rbtree.py) for sample usage.

# References

* [CLRS] Introduction to Algorithms 3rd Ed. Cormen, Thomas H. and Leiserson, Charles E. and Rivest, Ronald L. and Stein, Clifford, The MIT Press, 2001