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* pre-commit: Upgrade psf/black for stable style 2023 Updating https://github.com/psf/black ... updating 22.12.0 -> 23.1.0 for their `2023 stable style`. * https://github.com/psf/black/blob/main/CHANGES.md#2310 > This is the first [psf/black] release of 2023, and following our stability policy, it comes with a number of improvements to our stable style… Also, add https://github.com/tox-dev/pyproject-fmt and https://github.com/abravalheri/validate-pyproject to pre-commit. I only modified `.pre-commit-config.yaml` and all other files were modified by pre-commit.ci and psf/black. * [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci --------- Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
87 lines
2.5 KiB
Python
87 lines
2.5 KiB
Python
#!/usr/bin/env python3
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from .number_theory.prime_numbers import next_prime
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class HashTable:
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"""
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Basic Hash Table example with open addressing and linear probing
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"""
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def __init__(
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self,
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size_table: int,
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charge_factor: int | None = None,
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lim_charge: float | None = None,
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) -> None:
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self.size_table = size_table
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self.values = [None] * self.size_table
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self.lim_charge = 0.75 if lim_charge is None else lim_charge
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self.charge_factor = 1 if charge_factor is None else charge_factor
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self.__aux_list: list = []
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self._keys: dict = {}
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def keys(self):
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return self._keys
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def balanced_factor(self):
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return sum(1 for slot in self.values if slot is not None) / (
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self.size_table * self.charge_factor
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)
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def hash_function(self, key):
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return key % self.size_table
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def _step_by_step(self, step_ord):
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print(f"step {step_ord}")
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print(list(range(len(self.values))))
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print(self.values)
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def bulk_insert(self, values):
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i = 1
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self.__aux_list = values
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for value in values:
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self.insert_data(value)
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self._step_by_step(i)
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i += 1
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def _set_value(self, key, data):
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self.values[key] = data
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self._keys[key] = data
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def _collision_resolution(self, key, data=None):
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new_key = self.hash_function(key + 1)
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while self.values[new_key] is not None and self.values[new_key] != key:
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if self.values.count(None) > 0:
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new_key = self.hash_function(new_key + 1)
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else:
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new_key = None
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break
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return new_key
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def rehashing(self):
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survivor_values = [value for value in self.values if value is not None]
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self.size_table = next_prime(self.size_table, factor=2)
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self._keys.clear()
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self.values = [None] * self.size_table # hell's pointers D: don't DRY ;/
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for value in survivor_values:
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self.insert_data(value)
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def insert_data(self, data):
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key = self.hash_function(data)
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if self.values[key] is None:
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self._set_value(key, data)
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elif self.values[key] == data:
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pass
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else:
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collision_resolution = self._collision_resolution(key, data)
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if collision_resolution is not None:
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self._set_value(collision_resolution, data)
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else:
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self.rehashing()
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self.insert_data(data)
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