2026-06-01 18:12:40 +08:00
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#+ANKI_DECK: study_deck_02
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2026-06-01 17:12:10 +08:00
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* TODO 0020. Valid Parentheses :easy:
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2026-06-01 02:33:30 +08:00
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:PROPERTIES:
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2026-06-01 17:22:07 +08:00
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:NEETCODE: [[file:../../roadmap.org::*0020. Valid Parentheses][0020. Valid Parentheses]]
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2026-06-01 02:33:30 +08:00
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:END:
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2026-06-01 17:22:07 +08:00
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Given a string ~s~ containing just the characters ~'('~, ~')'~, ~'{'~, ~'}'~, ~'['~ and ~']'~, determine if the input string is valid.
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An input string is valid if:
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- Open brackets must be closed by the same type of brackets.
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- Open brackets must be closed in the correct order.
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- Every close bracket has a corresponding open bracket of the same type.
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*Example 1:*
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*Input:* s = "()"
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*Output:* true
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*Example 2:*
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*Input:* s = "()[]{}"
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*Output:* true
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*Example 3:*
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*Input:* s = "(]"
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*Output:* false
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*Example 4:*
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*Input:* s = "([])"
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*Output:* true
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*Example 5:*
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*Input:* s = "([)]"
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*Output:* false
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*Constraints:*
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- ~1 <= s.length <= 10^{4}~
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- ~s~ consists of parentheses only ~'()[]{}'~.
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2026-06-01 02:39:53 +08:00
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** TODO Approach
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Write your approach here.
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** TODO Python
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#+begin_src python
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2026-06-01 17:22:07 +08:00
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class Solution:
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def isValid(self, s: str) -> bool:
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2026-06-01 02:39:53 +08:00
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#+end_src
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** TODO C++
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2026-06-01 02:33:30 +08:00
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#+begin_src cpp
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2026-06-01 17:22:07 +08:00
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class Solution {
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public:
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bool isValid(string s) {
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}
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};
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2026-06-01 02:33:30 +08:00
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#+end_src
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