07 2018 档案
摘要：题目描述： Given an array of 2n integers, your task is to group these integers into n pairs of integer, say (a1, b1), (a2, b2), ..., (an, bn) which makes s
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摘要：题目描述： A self-dividing number is a number that is divisible by every digit it contains. For example, 128 is a self-dividing number because 128 % 1 == 0
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摘要：题目描述： Given a directed, acyclic graph of N nodes. Find all possible paths from node 0 to node N-1, and return them in any order. The graph is given as
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摘要：题目描述： Let's call an array A a mountain if the following properties hold: A.length >= 3 There exists some 0 < i < A.length - 1 such that A[0] < A[1] <
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摘要：问题描述： Given two binary trees and imagine that when you put one of them to cover the other, some nodes of the two trees are overlapped while the others
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摘要：题目描述： We are given the head node root of a binary tree, where additionally every node's value is either a 0 or a 1. Return the same tree where every s
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摘要：题目描述： Initially, there is a Robot at position (0, 0). Given a sequence of its moves, judge if this robot makes a circle, which means it moves back to
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摘要：题目描述： We have a two dimensional matrix A where each value is 0 or 1. A move consists of choosing any row or column, and toggling each value in that ro
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摘要：题目描述： Given a binary matrix A, we want to flip the image horizontally, then invert it, and return the resulting image. To flip an image horizontally m
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摘要：题目描述： The Hamming distance between two integers is the number of positions at which the corresponding bits are different. Given two integers x and y,
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摘要：题目描述： Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: Construct the maximum tree by the given a
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摘要：题目描述： International Morse Code defines a standard encoding where each letter is mapped to a series of dots and dashes, as follows: "a"maps to ".-", "b
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摘要：题目描述： Implement function ToLowerCase() that has a string parameter str, and returns the same string in lowercase. Example 1: Input: "Hello" Output: "h
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摘要：题目描述： In a 2 dimensional array grid, each value grid[i][j] represents the height of a building located there. We are allowed to increase the height of
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摘要：题目描述： You're given strings J representing the types of stones that are jewels, and S representing the stones you have. Each character in Sis a type of
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摘要：英文版的LeetCode经常性登陆不上，前面都是在牛客网上做的题目，但是每道题都是只有简单的描述，没有example，对于输入细节完全不知道。 还好今天LeetCode可以登陆，以后在LeetCode上做题。
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摘要：题目描述： Evaluate the value of an arithmetic expression in Reverse Polish Notation. Valid operators are+,-,*,/. Each operand may be an integer or another
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摘要：题目描述： 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 near
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