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Coding Problems

Coding problems are exercises designed to test a programmer’s ability to write logic, solve challenges and apply algorithms or data structures. They help improve problem-solving skills, logical thinking and coding efficiency. Common in interviews and competitive programming, coding problems range from simple tasks to complex algorithmic challenges, preparing developers for real-world software development scenarios.

Top Coding Problems Articles

Sliding Window Algorithm : Beginners to Advanced Engineers
Sliding Window Algorithm, What is the Sliding Window Approach?, Why Use Sliding Window? Where to Use Sliding Window, How Sliding Window Works with Examples
Check if a Linked List is Palindrome
Palindrome Linked List | Check if a Linked List is Palindrome O(n) time and O(1) space | Fast & Slow Pointer Method with In-Place Second Half Reversal
Amazon Transaction Logs
Amazon Transaction Logs (example question), Amazon Transaction Logs Interview question
2 Sum - Pair Sum Closest to 0
2 Sum - Pair Sum Closest to 0 , Sum of two elements whose sum is closest to zero , array DSA problem, coding problem , DSA coding problem , DSA interview coding problem
2 Sum – Count Pairs with given Sum in Sorted Array
2 Sum – Count Pairs with given Sum in Sorted Array, two sum , Count pairs with given sum , 2 sum problem , array DSA problem, coding problem , DSA interview coding problem
2 Sum Count pairs with given sum
2 Sum – Count pairs with given sum, two sum , Count pairs with given sum , 2 sum problem , array DSA problem, coding problem , DSA interview coding problem
Two Sum - Pair with given Sum
Two Sum – Pair with given Sum , 2 sum problem , array DSA problem, coding problem , DSA coding problem , DSA interview coding problem
Container With Most Water
Container With Most Water | You are given an integer array height of length n. There are n vertical lines drawn such that the two endpoints of the ith line are (i, 0) and (i, height[i]). Find two lines that together with the x-axis form a container such that the container contains the most water.
Maximum Product of Three Numbers
Maximum product of a triplet (subsequence of size 3) in array | Maximum Product of Three Numbers | Given an integer array arr, find three numbers whose product is maximum and return the maximum product.
3 Sum : Find triplets that add up to a target value
3 Sum : Find triplets that add up to a target value, 3 sum problem , Triplet Sum in Array , Given an integer array nums, return all the triplets that add up to a target value

Top Coding Problems Blogs

How to Find the Right View of a Binary Tree
Learn how to find the right view of a binary tree using DFS and BFS, with examples, code, complexity analysis and coding interview tips.
Left View of a Binary Tree: DFS and BFS Approaches Explained
Learn how to find the left view of a binary tree using DFS and BFS, with examples, code, complexity analysis, common mistakes and interview tips.
Top View of a Binary Tree Using BFS and DFS | Complete Guide
Learn how to find the top view of a binary tree using DFS and BFS with step-by-step explanations, examples, code, complexity analysis and interview insights.
Bottom View of a Binary Tree: DFS vs BFS Approach
Learn to find the bottom view of a binary tree using horizontal distance. Compares a buggy DFS attempt, a fixed DFS and the optimal BFS solution in Java.
Longest Playlist With No Repeated Songs : Brute Force to Optimal
Find the longest playlist with no repeated songs using brute force, HashSet, and HashMap sliding window techniques, with Java code and dry runs.
DSA Patterns for Coding Interviews: Complete LeetCode Roadmap (Beginner to Advanced)
Master every LeetCode pattern for coding interviews. Learn Arrays, Sliding Window, Graphs, Dynamic Programming, Trees, Heaps and more with 250+ curated problem
Maximum Productivity After Employee Rearrangement | Dynamic Programming Assignment Problem
Maximize team productivity after employee rearrangement using Dynamic Programming. Learn the key observation, DP state design, transitions, and O(N²) solution.
Minimum Cost to Sort an Array by Sorting Subarrays
Minimum Cost to Sort Array problem explained with brute force, optimal approach, chunks, DSA intuition, Java/C++/Python/C# solutions.
Contain Virus : Deep, Intuitive & Fully Explained Guide
Contain Virus problem explained with DFS + greedy approach, step-by-step simulation, examples and optimized solutions for coding interviews.
How Senior Devs Design Exception Patterns
Learn 7 advanced exception handling patterns senior developers use to build resilient systems beyond try-catch, including fail-fast, retries and structured logging.

Popular Topics

C# Collection
In C#, Collections are classes in the System.Collections and System.Collections.Generic namespaces that store and manage groups of related objects. They include types like List<T>, Dictionary<TKey,TValue>, Queue<T> and Stack<T>. Collections offer dynamic sizing, built-in search, sorting and iteration, making data handling efficient and flexible in C# applications.
Application Design
Application design is the process of planning and structuring an application’s architecture, user interface, data flow and functionality to meet user and business requirements. It involves decisions on technology stack, design patterns, scalability and security. Good application design ensures performance, maintainability and a seamless user experience across platforms and devices.
High-Level Design (HLD)
High-Level Design (HLD) outlines the system architecture and overall structure of a software solution. It defines components, modules, data flow, technologies and their interactions. HLD focuses on scalability, performance and reliability, serving as a bridge between requirements and Low-Level Design. It’s essential for planning system-wide decisions.
Interview Experience
An interview experience is a detailed account of the interview process for a specific role, covering rounds, questions asked, difficulty level, preparation tips and personal insights to help future candidates understand what to expect and how to prepare effectively.
Coding Problems
Coding problems are exercises designed to test a programmer’s ability to write logic, solve challenges and apply algorithms or data structures. They help improve problem-solving skills, logical thinking and coding efficiency. Common in interviews and competitive programming, coding problems range from simple tasks to complex algorithmic challenges, preparing developers for real-world software development scenarios.
Interview Preparation
Interview Preparation is the process of getting ready to perform confidently and effectively in a job interview. It includes researching the company, understanding the job role, practicing common interview questions, improving communication skills and reviewing technical or domain knowledge. Proper interview preparation increases confidence, reduces anxiety, and improves your chances of securing the job.
Language-Concepts
This tag is used to understand a basic part of the language.
Software Design
Software design is the process of planning and structuring a software system’s architecture, components, interfaces, and data flow to meet functional and non-functional requirements. It ensures scalability, maintainability and performance. Key approaches include modular design, object-oriented design and architectural patterns like MVC and microservices for efficient, reliable software development.
Math
math tag that is used for mathematical operations Math is the study of numbers, shapes, patterns and logical relationships. It provides tools for problem-solving, measurement and analysis across science, technology, engineering and daily life. Math includes fields like algebra, geometry, calculus and statistics. It builds critical thinking skills and forms the foundation for computing, algorithms, data science and modern technological advancements.
Interview Questions
Interview Questions are structured queries asked by employers to evaluate a candidate’s technical skills, problem-solving ability, experience, communication skills and cultural fit. These questions can include HR, behavioral, technical, coding and situational topics to assess whether the candidate is suitable for the job role and organization.
Popular Articles
Maximum Product Subarray, Find Maximum Product Subarray in an Array, Given an integer array arr, find a subarray that has the largest product,
Mastering the Template Design Pattern in C#, Template Design Pattern in Depth: Structure, Use Cases and Best Practices
Amazon Transaction Logs (example question), Amazon Transaction Logs Interview question
Mastering the Singleton Design Pattern in C#, Singleton Design Pattern in Depth: Structure, Use Cases and Best Practices, in depth design pattern, LLD , low level design
Top 50 SQL Interview Questions and Answers (Beginner to Intermediate). Top SQL Interview Questions for fresher. Frequently asked SQL interview questions with answers
Top High-Level Design(HLD) Interview Questions and answers, HLD QnA, HLD interview preparation
You are given two integer arrays arr1 and arr2, sorted in accending order, and two integers m and n, representing the number of elements in arr1 and arr2 respectively. Merge arr1 and arr2 into a single array sorted in accending order.
Find the Maximum Subarray Sum | Largest Sum Contiguous Subarray | Kadane’s Algorithm | Maximum Subarray | Given an integer array nums, find the subarray with the largest sum and return its sum | The Efficient Way to Find Maximum Subarray Sum
Learn how to create a primary key in SQL using syntax and examples. Ensure unique records, improve query performance and build table relationships.

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