随笔分类 - LeetCode
摘要：题目：求数组子集 Given a set of distinct integers, nums, return all possible subsets. Note: The solution set must not contain duplicate subsets. For example,I
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摘要：题目： Given a binary search tree, write a function kthSmallest to find the kth smallest element in it. Note: You may assume k is always valid, 1 ≤ k ≤ B
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摘要：题目： 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
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摘要：题目： Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the neare
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摘要：题目： Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tre
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摘要：题目： Write a function that takes an unsigned integer and returns the number of ’1' bits it has (also known as the Hamming weight). For example, the 32-
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摘要：题目： Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 分类：Tree Depth-first Search 代码：
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摘要：题目： Given an integer, write a function to determine if it is a power of three. Follow up:Could you do it without using any loop / recursion? 分类：Math 代
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摘要：题目： Given an integer, write a function to determine if it is a power of two. 判断是否是2的次方数 分类：Math Bit Manipulation 代码：
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摘要：题目： You are climbing a stair case. It takes n steps to reach to the top. Each time you can either climb 1 or 2 steps. In how many distinct ways can yo
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摘要：题目： Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order r
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摘要：题目： Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string. If the last
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摘要：题目：字符串匹配 Implement strStr(). Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. 分类：String Two P
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摘要：题目： Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal:
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摘要：题目： Compare two version numbers version1 and version2.If version1 > version2 return 1, if version1 < version2 return -1, otherwise return 0. You may a
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摘要：题目： The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ... 1 is read off as "one 1" or 11.11 is read
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摘要：题目： Write a function that takes a string as input and reverse only the vowels of a string. Example 1:Given s = "hello", return "holle". Example 2:Give
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摘要：题目： Given two binary strings, return their sum (also a binary string). For example,a = "11"b = "1"Return "100". 分类：String Math 代码：
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摘要：题目： Given two arrays, write a function to compute their intersection. Example:Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2, 2]. Note: Each el
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摘要：题目： Given two arrays, write a function to compute their intersection. Example:Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2]. Note: Each eleme
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