The problem looks simple at first, but it is a great example of how choosing the right data structure can make a solution both clean and efficient.

The goal is to determine whether a string containing (), {}, and [] is valid. Every opening bracket must have the correct closing bracket, and brackets must close in the proper order.

I solved it using a Stack. The approach is straightforward:

1. Create an empty stack.
2. Store matching closing brackets for each opening bracket.
3. Traverse the string character by character.
4. If the character is an opening bracket, push it onto the stack.
5. If it is a closing bracket, remove the most recent opening bracket using pop().
6. Check whether the opening and closing brackets match.
7. If they don't match, immediately return false.
8. At the end, the stack must be empty for the string to be valid.

This problem reinforced an important concept: Stacks are extremely useful whenever the most recently added element needs to be processed first (LIFO – Last In, First Out).

My submission achieved 0 ms runtime and passed 103/103 test cases. 💻🔥

Small problems like this are great for strengthening fundamental data-structure and problem-solving skills. One problem at a time, one concept at a time! 🚀

Tags:
#LeetCode #JavaScript #DSA #DataStructures #Algorithms #Stack #ValidParentheses #Coding #Programming #ProblemSolving #100DaysOfCode #CodingJourney #Developer #WebDevelopment #SoftwareEngineering