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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.

Problem Overview The HackerRank Jumping on the Clouds problem is a classic algorithmic challenge that tests your ability to make optimal decisions while traversing an array. You are given a

HackerRank Alternating Characters Problem Solution in C++ | Count Consecutive Duplicates

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

Problem Overview The HackerRank Alternating Characters problem requires you to remove the minimum number of characters from a string so that no two identical characters are adjacent. The goal is

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

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

Problem Overview The HackerRank Roads and Libraries problem is a classic graph problem where we need to build libraries and/or repair roads in a city to ensure that every citizen

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

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

Problem Overview The HackerRank Even Tree problem is a classic graph and tree problem that asks us to maximize the number of edges we can remove from a tree while

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

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

Problem Overview In LeetCode 172: Factorial Trailing Zeroes, we are asked to find the number of trailing zeros in a factorial of a given number n. This problem is a

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

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

Problem Overview In LeetCode 3163: String Compression III, we are asked to compress a string by replacing consecutive repeated characters with a count followed by the character. One important detail

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