HashMap in Java

Java program to count the occurrence of each character in a string using Hashmap - GeeksforGeeks

Govind Pothuraju on Instagram: "Day 20/200: How HashMap Works Internally HashMap is one of the most powerful data structures in coding interviews & real-world systems. Here’s how it works under the hood: ✅ Hashing: Key → Hash function → Index in array (bucket). ✅ Collision handling: Chaining (LinkedList/Tree in Java) or Open addressing. ✅ Time complexity: O(1) average for put/get, O(n) worst-case. ⚡ Mastering HashMap internals is a must for interviews — it shows depth, not just coding ability. F