递归,经典的八皇后问题. 利用一位数组存储棋盘状态,索引表示行,值为-1表示空,否则表示列数. 对行进行搜索,对每一行的不同列数进行判断,如果可以摆放符合规则,则摆放,同时遍历下一行. 遍历过程中,若已经遍历了n行,则保存该状态. Runtime: 4 ms, faster than 91.35% of C++ online submissions for N-Queens. class Solution { public: vector<vector<string>> res;…
The n-queens puzzle is the problem of placing n queens on an n×n chessboard such that no two queens attack each other. Given an integer n, return all distinct solutions to the n-queens puzzle. Each solution contains a distinct board configuration of…
作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 遍历 日期 题目地址:https://leetcode.com/problems/queens-that-can-attack-the-king/ 题目描述 On an 8x8 chessboard, there can be multiple Black Queens and one White King. Given an array of int…
https://leetcode.com/problems/generate-parentheses/ Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses. For example, given n = 3, a solution set is: "((()))", "(()())", "(())()&q…
The n-queens puzzle is the problem of placing n queens on an n×n chessboard such that no two queens attack each other. Given an integer n, return all distinct solutions to the n-queens puzzle. Each solution contains a distinct board configuration of…
题目: Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example: Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 return…
I Given a set of distinct integers, S, return all possible subsets. Note: Elements in a subset must be in non-descending order. The solution set must not contain duplicate subsets. For example,If S = [1,2,3], a solution is: [ [3], [1], [2], [1,2,3],…
题目: The n-queens puzzle is the problem of placing n queens on an n×n chessboard such that no two queens attack each other. Given an integer n, return all distinct solutions to the n-queens puzzle. Each solution contains a distinct board configuration…
题目如下: On an 8x8 chessboard, there can be multiple Black Queens and one White King. Given an array of integer coordinates queens that represents the positions of the Black Queens, and a pair of coordinates king that represent the position of the White…
/** * Merge two sorted linked lists and return it as a new list. * The new list should be made by splicing together the nodes of the first two lists. *//*由于链表只能从前向后添加的特点,所以从前边开始比较,小的添加进去每次递归确定一个node,需要确定两个值,一个是val,一个是next,next由下次递归确定 */ public ListNo…
Implement regular expression matching with support for '.' and '*'. '.' Matches any single character. '*' Matches zero or more of the preceding element. The matching should cover the entire input string (not partial). The function prototype should be…
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 off as "two 1s" or 21. 21 is read off as "one 2, then one 1" or 1211. Gi…
Follow up for N-Queens problem. Now, instead outputting board configurations, return the total number of distinct solutions. 思路1:打表 public class Solution { public int totalNQueens(int n) { int[] result = new int[] { 0, 1, 0, 0, 2, 10, 4, 40, 92, 352,…
[题目] Given a collection of distinct integers, return all possible permutations. 数组的组合情况. Input: [1,2,3] Output: [ [1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], [3,2,1] ] [思路] 求子集,排列组合的数组题有固定模板. [代码] class Solution { public List<List<Integer>> p…
Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example, "A man, a plan, a canal: Panama" is a palindrome. "race a car" is not a palindrome. Note: Have you consider that…
