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摘要： 题目：Follow up for N-Queens problem.Now, instead outputting board configurations, return the total number of distinct solutions.代码：class Solution {publi... 阅读全文

摘要： 题目：Then-queens puzzle is the problem of placingnqueens on ann×nchessboard such that no two queens attack each other.Given an integern, return all dist... 阅读全文

摘要： 题目：Follow up for "Unique Paths":Now consider if some obstacles are added to the grids. How many unique paths would there be?An obstacle and empty spac... 阅读全文

摘要： 题目：A robot is located at the top-left corner of amxngrid (marked 'Start' in the diagram below).The robot can only move either down or right at any poi... 阅读全文

摘要： 题目：Given a strings, partitionssuch that every substring of the partition is a palindrome.Return all possible palindrome partitioning ofs.For example, ... 阅读全文

摘要： 题目：Given a 2D board containing'X'and'O', capture all regions surrounded by'X'.A region is captured by flipping all'O's into'X's in that surrounded reg... 阅读全文

摘要： 题目：Given two words (startandend), and a dictionary, find all shortest transformation sequence(s) fromstarttoend, such that:Only one letter can be chan... 阅读全文

摘要： 题目：Given two words (beginWordandendWord), and a dictionary, find the length of shortest transformation sequence frombeginWordtoendWord, such that:Only... 阅读全文

摘要： 题目：Given a digit string, return all possible letter combinations that the number could represent.A mapping of digit to letters (just like on the telep... 阅读全文

摘要： 题目：Given two integersnandk, return all possible combinations ofknumbers out of 1 ...n.For example,Ifn= 4 andk= 2, a solution is:[ [2,4], [3,4], [2,... 阅读全文