98. Design HashMap

You're building a custom HashMap implementation. This is useful for understanding how hash maps work internally and for implementing custom key-value storage.

Design a HashMap without using any built-in hash table libraries.

Implement the MyHashMap class:

• MyHashMap() initializes the object with an empty map.
• void put(int key, int value) inserts a (key, value) pair into the HashMap. If the key already exists, update the value.
• int get(int key) returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key.
• void remove(int key) removes the key and its corresponding value if the map contains the mapping for the key.

Requirements

1. Basic Functionality

• Implement put, get, and remove operations
• Handle key collisions
• Efficient O(1) average time complexity
• Handle key updates

Example Usage

const map = new MyHashMap();
map.put(1, 1);
map.put(2, 2);
map.get(1);    // 1
map.get(3);    // -1
map.put(2, 1); // update
map.get(2);    // 1
map.remove(2);
map.get(2);    // -1

Real-World Context

This problem models real data structure implementation:

• Custom HashMap: Implement hash map from scratch
• Data structure design: Understand hash map internals
• Collision handling: Handle hash collisions
• Performance: O(1) average operations