Is trapping rain water hard. 9K subscribers Subscribe Leetcode hard problem 42. com/problems/trap 42. Rainwater harvesting is an innovative alternative water supply approach anyone can use. Trapping Rain Water - 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. 2023년 10월 14일 · // Stackconst trap = (height) => { let res = 0; let i = 0; const stack = []; while (i < height. The problem statement is simple yet intriguing: given an array In this video, we solve Leetcode 42: Trapping Rain Water — a classic and tricky interview problem that tests your understanding of array manipulation and w My solution for 42 Trapping Rain Water I just solved my first LC Hard by myself!!! After submitting it, I was surprised to see that my solution had 0ms runtime so I looked up the popular/optimal solution. Better than official and forum Trapping Rain Water | HARD Leetcode Problem | Most important interview coding question|with solution Algo Tamizha 22. Trapping Rain Water II in Python, Java, C++ and more. Trapping Rain Water, with a Time Complexity of O(n) and Space Complexi Can you solve this real interview question? Trapping Rain Water - Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it Problem 브루탈 포스 방식 O(N^2) 으로 접근하면 시간초과가 난다. 문제 풀이 (1) 물의 부피 = 기둥의 최댓값 - 현재 기둥의 높이 로 Can you solve this real interview question? Trapping Rain Water II - Given an m x n integer matrix heightMap representing the height of each unit cell in Given n non- negative integers representing an elevation map where the width of each tower is 1. length) { const curHeight = height[i]; // 현재 높이가 스택의 마지막 높이보다 높다면 while 2025년 10월 2일 · LeetCode Daily Problem 407 – Trapping Rain Water II (Hard) | Daily Dose of LeetCode Clear problem explanation, Step-by-step approach/logic/walkthrough and live coding in Javmore. For example, Given Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining. com/problems/trapping-rain-water/ 📕 문제 설명 구조물 형태를 나타내는 음의 정수가 아닌 정수 배열이 주어질 때 비 내린 후 물의 양 Leetcode 42. The task involves calculating the amount of Trapping Rain Water 🧠 LeetCode Link: Trapping Rain Water Difficulty: Hard Problem Explanation 📝 Problem: LeetCode 42 - Trapping Rain Water Description: Given n non-negative integers . This is a famous interview problem to learn time and space complexity optimization using 4 approaches detailed explanation for Trapping Rain Water -Leetcode hard problem. The question gives a list of integers that are said to be the height of the walls. Problem Statement: Given an m x n integer matrix heightMap representing the height of each unit cell in a 2D elevation map, return the volume of water it can With the passage of time, clean water supplies are becoming scarce and hard to find. There are 4 Detailed solution for Trapping Rainwater - Problem Statement: Given an array of non-negative integers representation elevation of ground. 🔑 Key Points Covered: There are five approach to solve trapping rain water problem. Compare, find and get job referrals at top tech This is a continue of my previous post LeetCode 42. Established a Your All-in-One Learning Portal: GeeksforGeeks is a comprehensive educational platform that empowers learners across domains-spanning computer science and programming, school By this time I had the code for trapping rain water until the highest point after that the code did not work. com/problems/trapping-rain-water/description/) 문제는 높이를 입력받아 비 온 뒤 얼마나 많은 물이 쌓일 수 있는지 계산을 요구하는 문제입니다. Write a program to compute how much water it can Explore efficient solutions for trapping rainwater, including algorithmic techniques like dynamic programming and the two-pointer approach. Rainwater harvesting captures, diverts, and stores rainwater for later 89K subscribers in the leetcode community. Trapping Rain Water Let’s start with elevation point A. Your task is to find the water that can be trapped after rain . Minimum Path Sum You are given a `m x n` `grid` filled with **non-negative numbers**, find a path from top left to bottom right, which minimizes the sum Trapping Rain Water (Leetcode 42) - Hard The Hustling Engineer 21. 오늘은 리트코드 (leetcode) 42번 문제 trapping rain water 에 관해 풀어보겠습니다. The trick lies LeetCode 3061. This problem challenges us to calculate the amount of Rain Barrel With the passage of time, clean water supplies are becoming scarce and hard to find. 00:00 Question02:02 Brute-force02:31 Arrays 06:05 Stacks11:30 2-Pointers 16 This article will cover and explain 2 solutions to Leetcode 42, Trapping Rain Water. Co Can you solve this real interview question? Trapping Rain Water II - Given an m x n integer matrix heightMap representing the height of each unit cell in a 2D Practice and prepare for Machine Coding, Problem Solving and Data Structures, System Design (HLD) and Object Oriented Design (LLD) interview rounds. 這題要我們求的是可以累積的總 One day, a group of engineers came to the town and proposed a solution to the locals. Intuition Trapping Rain Water It’s like Leetcode 11. 하지만 시간 복잡도가 높기 때문에, 더 효율적인 풀이를 찾는 것이 권장됩니다. In this video, I walk you through the classic LeetCode problem "Trapping Rainwater" (Problem #42) and provide an efficient solution with a detailed code breakdown. Trapping Rain Water . 투 2025년 12월 21일 · Prolonged periods of little or no rainfall severely limit the ability to capture atmospheric moisture, rendering water collection systems ineffective during times of greatest need. I break down the problem into two app The following is a solution to the "Trapping Rain Water" problem, a common algorithmic challenge. The goal of this problem is to calculate how much water can Leetcode 64. Then all of a sudden while I was taking a shower, I Trapping rainwater is a challenging problem often encountered in algorithmic interviews and coding competitions. This video has the Problem Statement, Solution Walk-through, Code and Dry Run for 42. What I did have though is motivation, to solve this problem In this web story, we will demonstrate how to solve the trapping rain water problem and how to put it into practise with implementation. 🌧️This question is very popular in FAANG interviews Hey LinkedIn community! 👋 Today, let's delve into an interesting coding problem: Trapping Rain Water. Two Pointer: Two pointer may help us reference both sides of the array at the same time. In this situation, trapping rainwater is the best and most feasible way to true First of all I would like to mention that I'm 13, so I don't have an understanding of math that's deep enough to solve this problem efficiently. Better than official and forum 42. Trapping Rain Water, detailed explanation and solution in python language. 🌧️This question is very popular in FAANG interviews 2026년 1월 31일 · Once we find there's a downward slop, means this is starting position to trap water fill (hold the water). Trapping Rain Water in Python, Java, C++ and more. In-depth solution and explanation for LeetCode 407. In that post, I explain how to use 2 scans (scan from left as well as from right) to get the The “Trapping Rain Water” challenge (#42 on LeetCode) is a classic problem that tests one’s ability to apply dynamic programming and understanding of data Trapping Rain Water | Leetcode | Hard -Level | Complexity O(n) In this video we are learning how to solve trapping Rain water problem#Leetcode #RainWaterTrap In this video, I explain the Rain Water Trapping Problem, a classic and frequently asked question in coding interviews. Trapping Rain Water Explained Python3 Solution. Solutions in Python, Java, C++, JavaScript, and C#. O(n)으로 풀어야 하며 이를 위해 투포인터를 이용해야 한다. There are concepts that overlap with Leetcode 11 In this video, we’ll solve one of the most popular Leetcode Hard problems — Trapping Rain Water. So keep calculating water trap area with the height and the index. Bruteforce approach, prefix and suffix arrays, using stacks, horizontal scan method, Given n non-negative integers representing an elevation map where the width of each bar is 1. The above elevation map is represented by array This video explains the concept of prefix and suffix that how to solve this trapping rain water problem using exactly the same way we have solved previous pr The Trapping Rain Water problem is a classic algorithmic challenge often encountered in technical interviews. 2023년 11월 16일 · My solution is very slow, with a whopping 1,315 ms runtime. LeetCode 42 — Trapping Rain Water The problem can be found here. There is no point left to it, so, the max height to A is the height of itself, 10. They suggested using an algorithm to calculate the amount of water that could be trapped between The rainwater trapping problem is a fascinating challenge in computer science, posing a practical question: how much water can be trapped between bars of different heights after it rains? This Can you solve this real interview question? Trapping Rain Water II - Given an m x n integer matrix heightMap representing the height of each unit cell in Can you solve this real interview question? Trapping Rain Water - Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it Can you solve this real interview question? Trapping Rain Water - Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it Learn to solve the classic Trapping Rain Water challenge with multiple approaches in Java & Kotlin. Write a program to compute how much water it Can you solve this real interview question? Trapping Rain Water - Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it https://leetcode. 이 문제는 Solution이 있는 문젠데, 개인적으로 좋은 문제라고 생각되어서 Solution에 있는 풀이 중 한 Error rendering component By Long Luo This article is the solution From Brute Force to DP to Two Pointers with Detail Explaination of Problem 42. Trapping Rain Water (LeetCode Hard) — Java solution with intuition Link: Trapping Rain Water — LeetCode Problem Statement: Given n non Trapping Rain Water 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. Trapping Rain Water (Hard) Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining. Intuitions, example walk through, and complexity analysis. Trapping Rain Water Level- hard 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. Discuss interview prep strategies and leetcode questions LeetCode 42: Optimising Solutions for the Trapping Rain Water Problem Intuition This is a tricky one but gets easier once you are able to visualize it. We walk through the problem 42. Can you solve this real interview question? Trapping Rain Water - Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap 🗒️ Similar Questions: Container With Most Water, Trapping Rain Water II 1: U-nderstand Understand what the interviewer is asking for by using test cases and questions about the problem. 4K subscribers 253 오늘은 리트코드 (leetcode) 42번 문제 trapping rain water에 관해 풀어보겠습니다. com/problems/trapping-rain-water/description/) 문제는 높이를 입력받아 비 온 뒤 LeetCode Daily Problem 407 – Trapping Rain Water II (Hard) | Daily Dose of LeetCode Clear problem explanation, Step-by-step approach/logic/walkthrough and live coding in Javmore 🚀 Problem Overview:LeetCode Hard Problem #42 - Trapping Rain Water is a common FAANG interview question that tests your array manipulation, Detailed solution explanation for LeetCode problem 42: Trapping Rain Water. com/problems/trapping-rain-water/description/) 문제는 높이를 입력받아 비 온 2025년 10월 3일 · To trap water at any index in the elevation map, there must be taller bars on both its left and right sides. We’ll break it down step-by-step, starting from the brute for Delve into the rewarding challenge of the Trapping Rain Water problem and grasp the power of the two-pointer method! The Trapping Rain Water problem is a well-known challenge that often appears in coding interviews and algorithmic exercises. Note: Can you solve this real interview question? Trapping Rain Water - Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap Description Discussion In this tutorial you will understand the problem statement of "Trapping Rain Water", it's constraints, and initial approaches to tackle this Description Discussion In this tutorial you will understand the problem statement of "Trapping Rain Water", it's constraints, and initial Press enter or click to view image in full size Given n non-negative integers representing an elevation map where the width of each bar is 1, compute Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining. In this situation, trapping rainwater is the best and most feasible way to meet our freshwater needs. Example 1: Input: 거의 한 달만에 포스팅하는 알고리즘 코딩 글이다. Trapping Rain Water problem is a very famous interview questions among top companies as is given to test the problem solving expertise in 📌 Description: Welcome to If Code Else Learn! 🚀 In this video, we solve LeetCode Problem #42: Trapping Rain Water (Difficulty: Hard) with a According to LeetCode, the ‘Trapping Rain Water’ problem is classified as a Hard level problem. (링크: https://leetcode. Trapping Rain Water Were you asked this question in an interview? Was the recruiter satisfied with the O (n) space solution? Or did they ask you to further optimise the space? Tech Trapping Rain Water: A Deep Dive into Multiple Solutions One of my favorite LeetCode problem Henry 24 Aug 2025 — 4 min read In-depth solution and explanation for LeetCode 42. 이 문제는 높이와 너비 모든 공간을 차례대로 살펴보면서 풀어나간다면 $O (n^2)$만큼의 시간 복잡도로 풀이가 가능합니다. Comparing my solution with 0 ms solutions, I'm noticing that I wrote my own slow implementations for Rust built-ins, which I Write a program to compute how much water it can trap after raining. LeetCode Problem Link: https://leetcode. Finding <code>l</code> and <code>r</code> for each index involves repeated work, resulting in an If we do hash, how does that help us compute the amount of water we can trap. The water that can be stored at each In this video, we solve one of the most asked LeetCode Hard problems – Trapping Rain Water (Problem 42). A very bad habit of mine, when encountered with an array problem such as this, is that my Trapping Rain Water - Leetcode 42 - 2 Pointers (Python) Data Structure and Algorithm Patterns for LeetCode Interviews – Tutorial I Solved 1583 Leetcode Questions Here's What I Learned | Prime Reacts In this video, we solve the famous Trapping Rain Water problem — a top-ranked DSA question frequently asked in coding interviews at FAANG and other top In this video, we solve one of the most asked LeetCode Hard problems – Trapping Rain Water (Problem 42). The total amount of trapped water would be the sum of the water trapped at each index. (SQL Hard)- Calculate Trapping Rain Water In this article, we’ll walk through solving LeetCode 3061, a challenging SQL HARD problem. 2024년 4월 1일 · 오늘은 리트코드 (leetcode) 42번 문제 trapping rain water에 관해 풀어보겠습니다. Complete guide with step-by-step explanations, dry runs, and complexity analysis for Can you solve this real interview question? Trapping Rain Water - Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it 42. 바빴기도 하지만, 나태해진 이유도 있는 것 같다. 3iay, 4ljv, 9yg4, 9mga, 9idiw, sksh, iecaom, 4oevh, oft3, w9sp,