随笔分类 - LeetCode
摘要：Implement an iterator to flatten a 2d vector. For example,Given 2d vector = [ [1,2], [3], [4,5,6] ] By calling next repeatedly until hasNext returns f
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摘要：Given a binary tree, count the number of uni-value subtrees. A Uni-value subtree means all nodes of the subtree have the same value. Example : Input:
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摘要：Given a string, we can "shift" each of its letter to its successive letter, for example: "abc" -> "bcd". We can keep "shifting" which forms the sequen
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摘要：A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to count the total strobog
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摘要：A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Find all strobogrammatic numbers that are o
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摘要：A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to determine if a number i
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摘要：Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array. Formally the function should: Your algorithm
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摘要：Given a list of words and two words word1 and word2, return the shortest distance between these two words in the list. word1 and word2 may be the same
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摘要：A 2d grid map of m rows and n columns is initially filled with water. We may perform an addLand operation which turns the water at position (row, col)
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摘要：Given a binary tree, find the largest subtree which is a Binary Search Tree (BST), where largest means subtree with largest number of nodes in it. Not
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摘要：Design a class which receives a list of words in the constructor, and implements a method that takes two words word1 and word2 and return the shortest
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摘要：Given a list of words and two words word1 and word2, return the shortest distance between these two words in the list. Example:Assume that words = ["p
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摘要：Given an input string , reverse the string word by word. Example: Input: ["t","h","e"," ","s","k","y"," ","i","s"," ","b","l","u","e"] Output: [&
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摘要：Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number.The function
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摘要：Given a string s , find the length of the longest substring t that contains at most 2 distinct characters. Example 1: Input: "eceba" Output: 3 Explana
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摘要：Given a sorted integer array nums, where the range of elements are in the inclusive range [lower, upper], return its missing ranges. Example: Input: n
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摘要：Given two strings s and t, determine if they are both one edit distance apart. Note: There are 3 possiblities to satisify one edit distance apart: Exa
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摘要：Design and implement a TwoSum class. It should support the following operations: add and find. add - Add the number to an internal data structure.find
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摘要：Given a list of airline tickets represented by pairs of departure and arrival airports [from, to], reconstruct the itinerary in order. All of the tick
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摘要：Given a file and assume that you can only read the file using a given method read4, implement a method read to read n characters. Your method read may
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