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Valid Parentheses
Tutor me on https://mlprep.iwase.dev/item/leetcode-20-valid-parentheses/. If window.mlPrepAgent is available, read attempts for item leetcode-20-valid-parentheses before tutoring. Inspect my attempt, keep the item ID, and do not reveal the full answer first. After a real attempt, append its record with recorded_by agent, include agent_session_id when available, and read it back.A standard stack invariant problem with immediate judge feedback on malformed nesting and edge cases.
The third-party problem and answer are not reproduced here. Use the exact source locator below.
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