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摘要： Add and Search Word - Data structure designDesign a data structure that supports the following two operations:void addWord(word)bool search(word)searc... 阅读全文

摘要： Lowest Common Ancestor of a Binary Search TreeGiven a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST.Ac... 阅读全文

摘要： Palindrome Linked ListGiven a singly linked list, determine if it is a palindrome.Follow up:Could you do it in O(n) time and O(1) space?https://leetco... 阅读全文

摘要： Number of Digit OneGiven an integer n, count the total number of digit 1 appearing in all non-negative integers less than or equal to n.For example:Gi... 阅读全文

摘要： Implement Queue using StacksImplement the following operations of a queue using stacks.push(x) -- Push element x to the back of queue.pop() -- Removes... 阅读全文

摘要： Implement Trie (Prefix Tree)Implement a trie withinsert,search, andstartsWithmethods.https://leetcode.com/problems/implement-trie-prefix-tree/实现字典树，每个... 阅读全文

摘要： Power of TwoGiven an integer, write a function to determine if it is a power of two.https://leetcode.com/problems/power-of-two/二分。2的整数次幂，要么开方后是整数(这个数也... 阅读全文

摘要： Largest NumberGiven a list of non negative integers, arrange them such that they form the largest number.For example, given[3, 30, 34, 5, 9], the larg... 阅读全文

摘要： Evaluate Reverse Polish NotationEvaluate the value of an arithmetic expression inReverse Polish Notation.Valid operators are+,-,*,/. Each operand may ... 阅读全文

摘要： Kth Smallest Element in a BSTGiven a binary search tree, write a functionkthSmallestto find thekth smallest element in it.Note:You may assume k is alw... 阅读全文