LeetCode Solution: 20. Valid Parentheses
The article explains the solution to LeetCode problem 20, Valid Parentheses, which involves determining if a string of brackets is correctly matched. The solution uses a stack data structure to track opening brackets and ensure they are closed in the correct order. The approach checks for matching pairs, proper sequence, and no unmatched brackets.
- ▪The problem requires checking if a string containing parentheses, curly braces, and square brackets is valid.
- ▪A valid string must have matching pairs, correct closing order, and no unmatched brackets.
- ▪The solution uses a stack to track opening brackets and a dictionary to map closing to opening brackets.
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| Original publisher | DEV.to (Top) |
| Canonical URL | https://dev.to/vansh_aggarwal_5fb2fff667/leetcode-solution-20-valid-parentheses-350j |
| Publication time | Sat, 16 May 2026 10:55:25 +0000 |
| Retrieval time | 2026-05-16T11:10:18.318Z |
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Opening excerpt (first ~120 words) tap to expand
try { if(localStorage) { let currentUser = localStorage.getItem('current_user'); if (currentUser) { currentUser = JSON.parse(currentUser); if (currentUser.id === 3840143) { document.getElementById('article-show-container').classList.add('current-user-is-article-author'); } } } } catch (e) { console.error(e); } Vansh Aggarwal Posted on May 16 LeetCode Solution: 20. Valid Parentheses #leetcode #dsa #programming #tutorial The Great Parentheses Puzzle: Cracking LeetCode 20 with Stacks! Hey there, future coding superstar! 👋 NavyaSree_14 here, and today we're diving into a classic LeetCode problem that might seem simple on the surface but teaches us a fundamental data structure concept: Valid Parentheses (Problem 20).
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Excerpt limited to ~120 words for fair-use compliance. The full article is at DEV.to (Top).
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