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"18. Subsets II" / "90. Subsets II" 本题难度: Medium Topic: Search & Recursion Description Given a collection of integers that might contain duplicates, n 阅读全文
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"33. N Queens" / "51. N Queens" 本题难度: Medium/Hard Topic: Search & Recursion Description The n queens puzzle is the problem of placing n queens on an n 阅读全文
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"127. Topological Sorting" 本题难度: Medium Topic: Search & Recursion Description Given an directed graph, a topological order of the graph nodes is defin 阅读全文
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"135. Combination Sum" / "39. Combination Sum" 本题难度: Medium Topic: Search & Recursion Description Given a set of candidate numbers (C) and a target nu 阅读全文
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"152. Combinations" / "77. Combinations" 本题难度: Medium Topic: Search & Recursion Description Given two integers n and k, return all possible combinatio 阅读全文
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"7. Serialize and Deserialize Binary Tree" / "297. Serialize and Deserialize Binary Tree" 本题难度: Medium/Hard Topic: Binary Tree Description Design an a 阅读全文
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"11. Search Range in Binary Search Tree" 本题难度: Medium Topic: Binary Tree Description Given a binary search tree and a range [k1, k2], return all eleme 阅读全文
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"700. Search in a Binary Search Tree" 本题难度: Easy Topic: Binary Tree Description Given the root node of a binary search tree (BST) and a value. You nee 阅读全文
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"73. Construct Binary Tree from Preorder and Inorder Traversal" /[105. Construct Binary Tree from Preorder and Inorder Traversal ](https://leetcode.co 阅读全文
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"95. Validate Binary Search Tree" / "98. Validate Binary Search Tree" 本题难度: Easy Topic: Binary Tree Description Given a binary tree, determine if it i 阅读全文