随笔分类 - Leetcode
摘要：For some fixed N, an array A is beautiful if it is a permutation of the integers 1, 2, ..., N, such that: For every i < j, there is no k with i < k <
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摘要：We are given S, a length n string of characters from the set {'D', 'I'}. (These letters stand for "decreasing" and "increasing".) A valid permutation
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摘要：In the video game Fallout 4, the quest "Road to Freedom" requires players to reach a metal dial called the "Freedom Trail Ring", and use the dial to s
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摘要：Given n balloons, indexed from 0 to n-1. Each balloon is painted with a number on it represented by array nums. You are asked to burst all the balloon
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摘要：Given a string of numbers and operators, return all possible results from computing all the different possible ways to group numbers and operators. Th
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摘要：Given a string that contains only digits 0-9 and a target value, return all possibilities to add binary operators (not unary) +, -, or * between the d
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摘要：Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times. You may assume that the
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摘要：984. String Without AAA or BBB Given two integers A and B, return any string S such that: S has length A + B and contains exactly A 'a' letters, and e
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摘要：Given an array A of 0s and 1s, divide the array into 3 non-empty parts such that all of these parts represent the same binary value. If it is possible
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摘要：Given an array A of integers, for each integer A[i] we need to choose either x = -K or x = K, and add x to A[i] (only once). After this process, we ha
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摘要：Given a string S of '(' and ')' parentheses, we add the minimum number of parentheses ( '(' or ')', and in any positions ) so that the resulting paren
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摘要：You want to form a target string of lowercase letters. At the beginning, your sequence is target.length '?' marks. You also have a stamp of lowercase
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摘要：The i-th person has weight people[i], and each boat can carry a maximum weight of limit. Each boat carries at most 2 people at the same time, provided
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摘要：Given two arrays A and B of equal size, the advantage of A with respect to B is the number of indices i for which A[i] > B[i]. Return any permutation
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摘要：A robot on an infinite grid starts at point (0, 0) and faces north. The robot can receive one of three possible types of commands: -2: turn left 90 de
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摘要：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 row or c
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摘要：At a lemonade stand, each lemonade costs $5. Customers are standing in a queue to buy from you, and order one at a time (in the order specified by bil
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摘要：Given a string S of digits, such as S = "123456579", we can split it into a Fibonacci-like sequence [123, 456, 579]. Formally, a Fibonacci-like sequen
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摘要：N couples sit in 2N seats arranged in a row and want to hold hands. We want to know the minimum number of swaps so that every couple is sitting side b
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摘要：A string S of lowercase letters is given. We want to partition this string into as many parts as possible so that each letter appears in at most one p
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