随笔分类 - LeetCode
摘要：Given an integer n, generate all structurally unique BST's (binary search trees) that store values 1 ... n. Example: Input: 3 Output: [ [1,null,3,2],
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摘要：Given n, how many structurally unique BST's (binary search trees) that store values 1 ... n? Example: Input: 3 Output: 5 Explanation: Given n = 3, the
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摘要：Given an array, rotate the array to the right by k steps, where k is non-negative. Example 1: Example 2: Note: Try to come up as many solutions as you
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摘要：Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2. Example 1: Input: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac" Output:
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摘要：Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only
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摘要：Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing its structure. Example 1: Input: [1,3,null,null,2
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摘要：Given a binary tree, return the inorder traversal of its nodes' values. Example: Input: [1,null,2,3] 1 \ 2 / 3 Output: [1,3,2] Follow up: Recursive so
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摘要：Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for the next level and
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摘要：Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. For example,
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摘要：Given inorder and postorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. For example,
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摘要：Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may comple
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摘要：Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. For this problem, a height-balanced bina
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摘要：Given an array where elements are sorted in ascending order, convert it to a height balanced BST. For this problem, a height-balanced binary tree is d
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摘要：Given two strings s and t, return the number of distinct subsequences of s which equals t. The test cases are generated so that the answer fits on a 3
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摘要：Given a binary tree, flatten it to a linked list in-place. For example,Given The flattened tree should look like: click to show hints. Hints: If you n
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摘要：Given a binary tree struct Node { int val; Node *left; Node *right; Node *next; } Populate each next pointer to point to its next right node. If there
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摘要：You are given a perfect binary tree where all leaves are on the same level, and every parent has two children. The binary tree has the following defin
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摘要：Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below. For example, given the fo
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摘要：The DNA sequence is composed of a series of nucleotides abbreviated as 'A', 'C', 'G', and 'T'. For example, "ACGAATTCCG" is a DNA sequence. When study
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摘要：Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may comple
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