This is an implementation of a Hashmap data structure in Python. The Hashmap class provides a way to store and retrieve key-value pairs efficiently using a hash function.
- Efficient Key-Value Storage: The Hashmap allows for quick insertion and retrieval of key-value pairs. The use of a hash function ensures that the time complexity for these operations is generally O(1), making it suitable for large datasets.
- Dynamic Resizing: The Hashmap automatically resizes itself when the load factor (the ratio of stored elements to the total capacity) exceeds a certain threshold. This ensures that the Hashmap can handle a growing number of elements without a significant performance impact.
- Collision Handling: In case of hash collisions (two different keys mapping to the same index), the implementation uses linear probing to find an empty slot in the bucket array. This allows for efficient handling of collisions and ensures that all key-value pairs can be stored correctly.
- Flexible Initial Capacity: The initial capacity of the Hashmap can be customized during instantiation. This allows users to choose an appropriate initial capacity based on their specific use case, optimizing memory usage.
- Constant Time Complexity: The average time complexity for insertion, retrieval, and deletion operations in a Hashmap is O(1). This makes it highly efficient for applications that require frequent data access and modification.
- Limited Key Types: The implementation relies on the keys being hashable objects. While most built-in Python types are hashable, custom objects need to implement the hash method to be used as keys. This limitation may restrict the types of keys that can be used in the Hashmap.
- Memory Overhead: The Hashmap uses an internal bucket array to store key-value pairs. If the initial capacity is set too high, it can result in wasted memory space. Additionally, the linear probing used for collision handling may lead to a higher number of empty slots in the bucket array, further increasing memory usage.
- No Ordering: The Hashmap does not provide any inherent ordering of its elements. If the order of elements is important, an alternative data structure, such as an OrderedDict, should be considered.
- Performance Degradation with High Collisions: If the hash function used produces a high number of collisions, the performance of the Hashmap can degrade. This is because finding an empty slot using linear probing may require traversing multiple elements, increasing the time complexity closer to O(n).
The Hashmap implementation presented here offers efficient key-value storage with dynamic resizing and collision handling. It provides a flexible and customizable solution for storing and retrieving data with constant time complexity for most operations. However, it is important to consider the limitations and potential performance issues when choosing this implementation for specific use cases.