Method _collision_resolution

data_structures/hashing/hash_table.py:179–237

This method is a type of open addressing which is used for handling collision. In this implementation the concept of linear probing has been used. The hash table is searched sequentially from the original location of the hash, if the new hash/location we get is alr

(self, key, data=None)

    @abstractmethod
    def _collision_resolution(self, key, data=None):
        """
        This method is a type of open addressing which is used for handling collision.

        In this implementation the concept of linear probing has been used.

        The hash table is searched sequentially from the original location of the
        hash, if the new hash/location we get is already occupied we check for the next
        hash/location.

        references:
            - https://en.wikipedia.org/wiki/Linear_probing

        Examples:
        1. The collision will be with keys 18 & 99, so new hash will be created for 99
        >>> ht = HashTable(3)
        >>> ht.insert_data(17)
        >>> ht.insert_data(18)
        >>> ht.insert_data(99)
        >>> ht.keys()
        {2: 17, 0: 18, 1: 99}

        2. The collision will be with keys 17 & 101, so new hash
        will be created for 101
        >>> ht = HashTable(4)
        >>> ht.insert_data(17)
        >>> ht.insert_data(18)
        >>> ht.insert_data(99)
        >>> ht.insert_data(101)
        >>> ht.keys()
        {1: 17, 2: 18, 3: 99, 0: 101}

        2. The collision will be with all keys, so new hash will be created for all
        >>> ht = HashTable(1)
        >>> ht.insert_data(17)
        >>> ht.insert_data(18)
        >>> ht.insert_data(99)
        >>> ht.keys()
        {2: 17, 3: 18, 4: 99}

        3. Trying to insert float key in hash
        >>> ht = HashTable(1)
        >>> ht.insert_data(17)
        >>> ht.insert_data(18)
        >>> ht.insert_data(99.99)
        Traceback (most recent call last):
        ...
        TypeError: list indices must be integers or slices, not float
        """
        new_key = self.hash_function(key + 1)

        while self.values[new_key] is not None and self.values[new_key] != key:
            if self.values.count(None) > 0:
                new_key = self.hash_function(new_key + 1)
            else:
                new_key = None
                break