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Hackerrank Sales By Mach Problem Solution in Python & Java

OJ Solutions | Sept. 30, 2025, 2:05 a.m.

Problem Overview The Sales By Mach problem on HackerRank is a classic counting problem. You are given a pile of socks, each with a color represented by an integer. The

LeetCode Add Two Numbers Problem Solution in C++, Python & Java

OJ Solutions | Sept. 25, 2025, 12:57 a.m.

Problem Overview The Add Two Numbers problem on LeetCode involves working with linked lists. You are given two non-empty linked lists representing two non-negative integers. The digits are stored in

LeetCode Two Sum Problem Solution in C++ and Go

OJ Solutions | Sept. 25, 2025, 12:40 a.m.

Problem Overview The Two Sum problem on LeetCode is one of the most popular beginner-friendly problems. It asks us to find two distinct indices in an array such that the

Counting Valleys HackerRank Solution in Python & Java | Step-by-Step Guide

OJ Solutions | Sept. 22, 2025, 12:41 a.m.

Problem Overview The Counting Valleys problem on HackerRank asks you to determine how many valleys a hiker walks through during a hike. The hiker's path is represented as a string

HackerRank Repeated String Problem Solution in C++ | Count 'a' Efficiently

OJ Solutions | Sept. 21, 2025, 8:58 a.m.

Problem Overview The Repeated String problem on HackerRank asks you to determine how many times the letter 'a' appears in the first n characters of an infinitely repeated string. You

HackerRank Jumping on the Clouds Problem Solution in Python & Java | Minimum Jumps Algorithm

OJ Solutions | Sept. 11, 2025, 4:18 p.m.

Why Solving HackerRank Jumping on the Clouds Problem Is Important? Array and greedy problems like HackerRank Jumping on the Clouds are more than just coding exercises—they help you develop strong

HackerRank Alternating Characters Solution in C++ | Approaches & Optimization

OJ Solutions | Sept. 11, 2025, 3:50 p.m.

Why Solving HackerRank Alternating Characters Problem Is Important? String problems like HackerRank Alternating Characters are more than just coding puzzles—they strengthen your understanding of string manipulation, consecutive duplicate detection, and

HackerRank Roads and Libraries Problem Solution in C++ | DFS Approach Explained

OJ Solutions | Aug. 19, 2025, 5:38 p.m.

Why Solving HackerRank’s Roads and Libraries Problem Is Important Graph-based challenges like HackerRank Roads and Libraries are not just about building libraries or repairing roads—they strengthen your graph traversal, connected

Even Tree HackerRank Problem Solution in C++ with Step-by-Step Explanation

OJ Solutions | Aug. 19, 2025, 4:33 p.m.

Why Solving HackerRank’s “Even Tree” Problem Is Important? Tree-based challenges like HackerRank’s Even Tree problem go far beyond counting edges or performing simple traversals—they strengthen your logical reasoning, recursive thinking,

LeetCode 172 Factorial Trailing Zeroes Solution – C++ Implementation and Explanation

OJ Solutions | Aug. 16, 2025, 5:23 p.m.

Why Solving LeetCode 172 – Factorial Trailing Zeroes Is Important? Mathematical problems like LeetCode 172: Factorial Trailing Zeroes are not just about finding the number of zeros in a factorial—they

LeetCode 3163 String Compression III Solution – C++ Implementation and Explanation

OJ Solutions | Aug. 14, 2025, 6:15 p.m.

Why Solving LeetCode 3163: String Compression III in C++ is Important? LeetCode 3163, String Compression III, is more than just a coding challenge—it's a practical exercise in C++ string manipulation

LeetCode 185 Department Top Three Salaries Solution Explained

OJ Solutions | Aug. 14, 2025, 5:46 p.m.

Why Solving Department Top Three Salaries SQL Problem is Important SQL problems like LeetCode 185: Department Top Three Salaries are not just exercises—they are essential for mastering SQL query writing