LeetCode 380: Insert Delete GetRandom O(1) | Java Solution | HashMap + ArrayList

Описание: This problem challenges you to design a data structure that supports inserting, deleting, and getting a random element - all in O(1) time complexity! #leetcode #datastructure #hashmap #arraylist

*Time Complexity:* O(1) for all operations
*Space Complexity:* O(n) where n is the number of elements stored

⏱️ Timestamps
00:00 - Understanding problem statement
01:01 - Analyzing data structures
03:45 - Java code walk-through
05:43 - Solution analysis - runtime + memory

🔍 Key Concepts
Design problems
Random access in O(1) time
Hybrid data structures
HashMap and ArrayList integration
Constant time operations

💡 Learning Points
How to combine multiple data structures to achieve specific time complexity goals
Efficient techniques for handling random retrieval with O(1) guarantee
Trade-offs between different data structures
Interview-style implementation of a custom data structure

🔗 Related LeetCode Problems
LeetCode 381: Insert Delete GetRandom O(1) - Duplicates allowed
LeetCode 146: LRU Cache
LeetCode 460: LFU Cache
LeetCode 432: All O`one Data Structure

👥 Target Audience
This video is designed for software engineers preparing for technical interviews and those interested in advanced data structure design patterns.

📚 Prerequisites
Basic understanding of Java
Familiarity with HashMaps and ArrayLists
Understanding of time and space complexity

🔗 Links
Problem: https://leetcode.com/problems/insert-...
Solution code: https://leetcode.com/problems/insert-...

💡 Additional Tips
Pay special attention to how we maintain O(1) deletion time by swapping elements
Focus on the limitations of various data structures and why a hybrid approach is necessary
Consider the random element retrieval implementation using Math.random() and its implications

🔔 Like, subscribe, and leave your questions or solution approaches in the comments! I respond to every comment and would love to hear your insights on this problem or requests for future videos. #codinginterviews #javaprogram #algorithmdesign