20. Valid Parentheses | LeetCode | Dart

Welcome back to our coding interview prep series! In today's video, we'll tackle the popular LeetCode problem "Valid Parentheses". This is a classic question often asked in coding interviews to test your understanding of data structures and your problem-solving skills. We'll break down the problem, discuss the approach, and implement the solution in Dart. 🔍 Problem Description: The "Valid Parentheses" problem asks us to determine if a given string of parentheses (which may include '()', '{}', and '[]') is valid. A string is considered valid if: Open brackets are closed by the same type of brackets. Open brackets are closed in the correct order. 🧩 Key Concepts Covered: Stack Data Structure: We'll use a stack to keep track of the opening brackets and ensure they are closed in the correct order. String Traversal: We'll iterate through the string to process each character. Condition Checking: We'll check for matching pairs and ensure the stack is appropriately managed. 💻 Dart Implementation: We'll write a clean and efficient Dart function to solve the problem. Here's a quick overview of the steps: Initialize an empty stack using a List in Dart. Create a Map to map closing brackets to their corresponding opening brackets. Iterate through the string using a for loop: If it's an opening bracket, add it to the stack. If it's a closing bracket, check if it matches the top of the stack using the last property. After processing the string, check if the stack is empty using the isEmpty property. 📘 Chapters: 00:00 - Problem Statement 01:50 - Explaining Approach 05:50 - Writing Code 13:02 - Running & Submitting 13:35 - Conclusion 🏷️Tags: #LeetCode #ValidParentheses #Dart #CodingInterview #Programming #TechInterview #DataStructures #Algorithms #Coding