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@mRcOol7 mRcOol7 commented Oct 7, 2024

Here's a structured format for your pull request, incorporating your details along with placeholders for the checklist and description. You can copy and paste this directly into your PR:


Title

Implement Fibonacci Heap with Core Operations

Description

This pull request implements the FibonacciHeap data structure in Python, featuring core operations such as insert, extract_min, decrease_key, and delete. The implementation includes a Node class to represent each heap node and optimizes for amortized time complexity, providing efficient operations crucial for algorithms like Dijkstra's.

  • Implemented FibonacciHeap with core operations: insert, extract_min, decrease_key, and delete.
  • Added Node class for heap node structure.
  • Optimized for amortized time complexity with O(1) inserts and O(log n) extract min.
  • Included example usage and basic documentation.

Describe your change:

  • Add an algorithm?
  • Fix a bug or typo in an existing algorithm?
  • Add or change doctests? -- Note: Please avoid changing both code and tests in a single pull request.
  • Documentation change?

Checklist:

  • I have read CONTRIBUTING.md.
  • This pull request is all my own work -- I have not plagiarized.
  • I know that pull requests will not be merged if they fail the automated tests.
  • This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
  • All new Python files are placed inside an existing directory.
  • All filenames are in all lowercase characters with no spaces or dashes.
  • All functions and variable names follow Python naming conventions.
  • All function parameters and return values are annotated with Python type hints.
  • All functions have doctests that pass the automated testing.
  • All new algorithms include at least one URL that points to Wikipedia or another similar explanation.
  • If this pull request resolves one or more open issues, then the description above includes the issue number(s) with a closing keyword: "Fixes #ISSUE-NUMBER".

Feel free to check or uncheck items in the checklist according to the current status of your pull request. If you have an issue number, you can also add it to the description section as "Fixes #". Let me know if you need any more adjustments!

- Implemented `FibonacciHeap` with core operations: `insert`, `extract_min`, `decrease_key`, and `delete`.
- Added `Node` class for heap node structure.
- Optimized for amortized time complexity with O(1) inserts and O(log n) extract min.
- Included example usage and basic documentation.
@algorithms-keeper algorithms-keeper bot added require tests Tests [doctest/unittest/pytest] are required require type hints https://docs.python.org/3/library/typing.html labels Oct 7, 2024
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Repository:

Python:

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@@ -0,0 +1,173 @@
class Node:
def __init__(self, key):

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Please provide return type hint for the function: __init__. If the function does not return a value, please provide the type hint as: def function() -> None:

Please provide type hint for the parameter: key

self.prev = self # Pointer to the previous node in the circular list

class FibonacciHeap:
def __init__(self):

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Please provide return type hint for the function: __init__. If the function does not return a value, please provide the type hint as: def function() -> None:

self.min_node = None # Pointer to the minimum node
self.num_nodes = 0 # Number of nodes in the heap

def insert(self, key):

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Please provide return type hint for the function: insert. If the function does not return a value, please provide the type hint as: def function() -> None:

As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function insert

Please provide type hint for the parameter: key

self.min_node = new_node
self.num_nodes += 1

def _insert_to_root_list(self, node):

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Please provide return type hint for the function: _insert_to_root_list. If the function does not return a value, please provide the type hint as: def function() -> None:

As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function _insert_to_root_list

Please provide type hint for the parameter: node

self.min_node.prev.next = node
self.min_node.prev = node

def extract_min(self):

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Please provide return type hint for the function: extract_min. If the function does not return a value, please provide the type hint as: def function() -> None:

As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function extract_min

@algorithms-keeper algorithms-keeper bot added the awaiting reviews This PR is ready to be reviewed label Oct 7, 2024
@algorithms-keeper algorithms-keeper bot added the tests are failing Do not merge until tests pass label Oct 7, 2024
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Click here to look at the relevant links ⬇️

🔗 Relevant Links

Repository:

Python:

Automated review generated by algorithms-keeper. If there's any problem regarding this review, please open an issue about it.

algorithms-keeper commands and options

algorithms-keeper actions can be triggered by commenting on this PR:

  • @algorithms-keeper review to trigger the checks for only added pull request files
  • @algorithms-keeper review-all to trigger the checks for all the pull request files, including the modified files. As we cannot post review comments on lines not part of the diff, this command will post all the messages in one comment.

NOTE: Commands are in beta and so this feature is restricted only to a member or owner of the organization.

return min_node.key
return None

def _consolidate(self) -> None:

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As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function _consolidate

if self.min_node is None or node.key < self.min_node.key:
self.min_node = node

def _link(self, node1: Node, node2: Node) -> None:

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As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function _link

if node.key < self.min_node.key:
self.min_node = node

def _cut(self, node: Node, parent: Node) -> None:

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As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function _cut

node.parent = None
node.is_marked = False

def delete(self, node):

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Please provide return type hint for the function: delete. If the function does not return a value, please provide the type hint as: def function() -> None:

As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function delete

Please provide type hint for the parameter: node

self.decrease_key(node, float('-inf')) # Decrease the key to -infinity
self.extract_min() # Extract the minimum node

def is_empty(self):

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Please provide return type hint for the function: is_empty. If the function does not return a value, please provide the type hint as: def function() -> None:

As there is no test file in this pull request nor any test function or class in the file data_structures/heap/fibonacci_heap.py, please provide doctest for the function is_empty

@mRcOol7 mRcOol7 closed this Oct 21, 2024
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