I wrote a compact LRU (Least Recently Used) cache implementation using LinkedHashMap’s “access order” feature. In an LRU cache, the eviction policy is to evict entries which have been accessed the longest time ago. LinkedHashMap maintains a doubly linked list of entries internally which is by default in insertion order…

Just wanted to jot down some notes on Java’s ArrayList [1] Capacity attribute is a performance hint. ArrayList will grow or shrink dynamically irrespective of what the capacity is set to. [2] Having capacity set does not mean you can read or write to an index which has not been…

I came across a note in TreeSet’s javadoc which intrigued me: “Note that the ordering maintained by a set (whether or not an explicit comparator is provided) must be consistent with equals if it is to correctly implement the Set interface.” What does that mean? The TreeSet doc says to…

This post is one in the series of posts about Scala. My goal is to provide simple examples to illustrate important gotchas or points about the language. Function Return Type Return type is optional, but it’s better to declare it because compiler may not be able to infer it to…

https://leetcode.com/problems/minimum-cost-to-connect-sticks/ You have some sticks with positive integer lengths. You can connect any two sticks of lengths X and Y into one stick by paying a cost of X + Y. You perform this action until there is one stick remaining. Return the minimum cost of connecting all the given…