Factory Method is a creational design pattern that deals with the object creation. It separates the object creation logic from the client code, which makes the system more flexible and maintainable. Instead of instantiating objects directly using a constructor, it passes the responsibility to another method, which is called a factory method. In contrast, if […]
August 26, 2025 | Factory Method Design Pattern, Object Oriented Design Patterns | No comments
You are given two singly linked lists that intersect at some node. Your task is to find and return the first intersecting node.
March 11, 2025 | Data Structure, Google | No comments
A builder plans to construct N houses in a row, where each house can be painted in K different colors. The goal is to minimize the total painting cost, ensuring that no two adjacent houses have the same color.
March 9, 2025 | Data Structure, dsa, Facebook | No comments
Find the length of the longest absolute path to a file within the abstracted file system. The length is measured in characters.
February 19, 2025 | dsa, Google | No comments
You manage an e-commerce website and need to keep track of the last N order IDs in a log. Design a data structure that supports the following operations efficiently:
February 6, 2025 | Data Structure, dsa, Twitter | No comments
You are given a stream of elements that is too large to fit into memory. Write an algorithm to select a random element from the stream with equal probability
February 3, 2025 | Algorithm, dsa, Twitter | No comments
The formula for the area of a circle is given by πr². Use the Monte Carlo method to approximate the value of π to three decimal places.
January 17, 2025 | dsa, DSA Sheet, Google | No comments
Given an integer k and a string s, write a function to determine the length of the longest substring in s that contains at most k distinct characters.
January 16, 2025 | Amazon, dsa, DSA Sheet | No comments
There is a staircase with N steps, and you can ascend either 1 step or 2 steps at a time. Write a function to calculate the number of unique ways to climb the staircase. The sequence of steps matters.
January 11, 2025 | Amazon, Data Structure, dsa | No comments
Build an autocomplete system that, given a query string s and a set of possible query strings returns all strings from the set that start with s as a prefix.
January 10, 2025 | dsa, DSA Sheet, Twitter | No comments