DSA

🔗LC2694 🟡 Medium 🧩 Pattern – Classes and Arrays 📅 Day 28/30 Days of JavaScript Design an EventEmitter class. This interface is similar (but with some differences) to the one found in Node.js or the Event Target interface of the DOM. The EventEmitter should allow for subscribing to events and emitting… Read More »Event Emitter – 2694

🔗LC2705 🟡 Medium 🧩 Pattern – JSON, Arrays and Objects 📅 Day 27/30 Days of JavaScript Given an object or array obj, return a compact object. A compact object is the same as the original object, except with keys containing falsy values removed. This operation applies to the object and any nested… Read More »Compact Object – 2705

🔗LC2625 🟡 Medium 🧩 Pattern – JSON, Arrays and Objects 📅 Day 26/30 Days of JavaScript Given a multidimensional array arr and a depth n, return a flattened version of that array. A multidimensional array is a recursive data structure that contains integers or other multidimensional arrays. A flattened array is a version of that array with some or all of… Read More »Flatten Deeply Nested Array – 2625

🔗LC2722 🟡 Medium 🧩 Pattern – JSON, Arrays and JS Sort 📅 Day 25/30 Days of JavaScript Given two arrays arr1 and arr2, return a new array joinedArray. All the objects in each of the two inputs arrays will contain an id field that has an integer value.  joinedArray is an array formed by merging arr1… Read More »Join Two Arrays by ID – 2722

🔗LC2724 🟢 Easy 🧩 Pattern – JSON, Arrays and JS Sort 📅 Day 24/30 Days of JavaScript Given an array arr and a function fn, return a sorted array sortedArr. You can assume fn only returns numbers and those numbers determine the sort order of sortedArr. sortedArr must be sorted in ascending order… Read More »Sort By – 2724

🔗LC2631 🟡 Medium 🧩 Pattern – JSON, Objects and Arrays 📅 Day 23/30 Days of JavaScript Write code that enhances all arrays such that you can call the array.groupBy(fn) method on any array and it will return a grouped version of the array. A grouped array is an object where each key is the output of… Read More »Group By – 2631