Orz yjc 吊打候选队 不好的思路是枚举森林的m块,这样DP显然会涉及n当做某一维,最多只能卷积优化一下 生成函数什么的n太大不用想 考虑m,k比较小,能不能把n变成一个系数,而不是维度 所以就是m的选择以及度数的情况,剩下的n接上去. https://blog.csdn.net/qq_39972971/article/details/94048092 这个森林的prufer序列,也可以用n+1作为大根来连接m个儿子(这样比较自然) 本质显然是一样的 转化为序列问题 枚举总共的度数是i的话…

时间限制:10000ms 单点时限:1000ms 内存限制:256MB 描述 A company plans to recruit some new employees. There are N candidates (indexed from 1 to N) have taken the recruitment examination. After the examination, the well-estimated ability value as well as the expected…

Number of Islands Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are…

要求 给定一个二维数组,只有0和1两个字符,1代表陆地,0代表水域,纵向和横向的陆地连接成岛屿,被水域隔开,求出地图中有多少岛屿 思路 对要查找的区域进行双重循环遍历,寻找陆地 从陆地初始点开始进行深度优先遍历 如:从(0,0)开始深度遍历,填充岛屿,(0,1)已经访问过,(0,2)为水域,直到(2,2)再开始深度遍历 实现 res:有多少个岛屿 递归条件:在区域内,未被访问过,是陆地 终止条件融入到了if语句中 1 class Solution { 2 3 private: 4 int d[4…

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) into a land. Given a list of positions to operate, count the number of islands after each addLand o…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…

Given a boolean 2D matrix, find the number of islands. Notice 0 is represented as the sea, 1 is represented as the island. If two 1 is adjacent, we consider them in the same island. We only consider up/down/left/right adjacent. Have you met this ques…

(1)Island Perimeter 解题思路: 在矩阵上循环并记录岛(1)的个数;如果当前节点是岛,则检查其是否具有任何右邻居或下邻居,有的话邻居计数加1 ;岛的周长结果为islands * 4 - neighbors * 2.(乘2的原因是因为一条边属于两个邻居). 代码如下: public class Solution { public int islandPerimeter(int[][] grid) { int islands = 0; int neighbours =0; for…

题目: 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) into a land. Given a list of positions to operate, count the number of islands after each addLa…

题目: Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded…