Longest Valid Parentheses – Leetcode 32 Solution

The Longest Valid Parentheses Leetcode problem is a classic string problem that tests your ability to work with parentheses and logic structures. Here’s the problem statement: Given a string containing just the characters ‘(‘ and ‘)’, find the length of the longest valid (well-formed) parentheses substring. This blog post will walk you through several approaches … Read more

Find the Index of the First Occurrence in a String

LeetCode problem 28, “Find the Index of the First Occurrence in a String“, asks us to locate the first index of a given substring (needle) in another string (haystack). If the substring is not found, we return -1. This is a classic problem in string searching with multiple approaches ranging from basic brute force to … Read more

Remove Element-Leetcode 27 Solution

The Remove Element problem is a classic LeetCode challenge. The task is to remove all occurrences of a specified value (val) from an integer array nums in-place and return the count of the remaining elements. Here’s a comprehensive guide to solving the problem, covering all approaches from naive to optimal. Problem Statement Given an integer … Read more

Remove Duplicates From Sorted Array-Leetcode 26 Solution

The “Remove Duplicates from Sorted Array” problem is a classic exercise on LeetCode that tests your ability to manipulate arrays efficiently. The task involves removing duplicate elements from a sorted array and returning the length of the modified array without using extra space for another array. This guide explores multiple approaches, from naive to optimal, … Read more

Remove Nth Node from End of List | Leetcode 19 Solution

Problem Description Given a linked list, remove nth node from end of list and return its head. The list can have various sizes, and the node we need to remove can be anywhere from the beginning to the end of the list. Approach To solve this problem efficiently, we need to think about how to … Read more

4Sum Leetcode | Leetcode 18 Solution

The 4Sum problem is a variation of the classic two-sum problem. The task is to find all unique quadruplets in an array that sum up to a target value. This problem is often encountered in coding interviews and algorithm competitions. In this blog post, we will discuss various solutions for the 4Sum problem, ranging from … Read more

3Sum Closest | Leetcode 16 Solution

The 3Sum Closest problem from Leetcode is a popular algorithmic challenge that tests your understanding of array manipulation and optimization techniques. In this article, we’ll cover the problem statement, a step-by-step approach to solving it, and explain multiple solutions from naive to optimized with their complexities. We’ll also provide well-commented Java code for each solution. … Read more

Median of Two Sorted Arrays | Leetcode 4

median of two sorted arrays

Finding the median of two sorted arrays is a classic problem in computer science and competitive programming. It is particularly interesting due to its constraints, which encourage an efficient solution rather than a simple brute-force approach. In this article, we’ll cover different methods to solve this problem, including their pros and cons, and provide Java … Read more

Master Two Pointer Technique: A Complete Guide

Two Pointers Technique

In this article, we will explore the Two Pointer pattern in detail. We’ll discuss what it is, when to use it, and go through some classic examples to illustrate how powerful it can be. What is the Two Pointer Technique in Coding? The Two Pointer technique is a pattern where two pointers (or indices) are … Read more

Leetcode 42 – Trapping Rain Water | Two Pointer

Trapping Rain Water

Problem Description: Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap after raining. Example 1 : Example 2: Constraints: Problem Link :Trapping Rain Water – LeetCode Solution(s): Approach 1: Brute Force Solution Java Code: Explanation: 1.Initialization: 2.Main Loop: 3.Finding Maximum Height to the Left: … Read more