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
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
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
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
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
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
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
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
The Sliding Window Maximum is a common algorithm problem where, given an array of integers and a window size k, you are asked to find the maximum number in each sliding window of size k as the window moves from left to right across the array. Problem Description for Sliding Window Maximum: You are given … Read more
The Sliding Window technique is a powerful and efficient method used to solve problems involving arrays, strings, and sequences. Instead of using brute force methods that may result in time complexity issues, sliding window optimizes the process by reducing redundant calculations, making it a popular approach among competitive programmers. In this guide, we’ll break down … Read more