P2212 [USACO14MAR]浇地Watering the Fields 题目描述 Due to a lack of rain, Farmer John wants to build an irrigation system to send water between his N fields (1 <= N <= 2000). Each field i is described by a distinct point (xi, yi) in the 2D plane, with 0 &…

P2212 [USACO14MAR]浇地Watering the Fields 题目描述 Due to a lack of rain, Farmer John wants to build an irrigation system to send water between his N fields (1 <= N <= 2000). Each field i is described by a distinct point (xi, yi) in the 2D plane, with 0 &…

传送门 题解:计算欧几里得距离,Krusal加入边权大于等于c的边,统计最后树的边权和. 代码: #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define maxn 2009 using namespace std; int n,c,cnt,tot,ans; int xi[maxn],yi[maxn],fa[maxn]; struct Edge{ int…

P2212 [USACO14MAR]浇地Watering the Fields 题目描述 Due to a lack of rain, Farmer John wants to build an irrigation system to send water between his N fields (1 <= N <= 2000). Each field i is described by a distinct point (xi, yi) in the 2D plane, with 0 &…

https://www.luogu.org/problem/show?pid=2212 题目描述 Due to a lack of rain, Farmer John wants to build an irrigation system to send water between his N fields (1 <= N <= 2000). Each field i is described by a distinct point (xi, yi) in the 2D plane, with…

题目链接: https://www.luogu.org/problemnew/show/P2212 思路: 一道最小生成树裸题(最近居然变得这么水了),但是因为我太蒻,搞了好久,不过借此加深了对最小生成树的认识. 首先这明显是个稠密图,有\(\sum_{n-1}^{i=1}i=n*(n-1)/2\)条边,看起来\(Prim\)会明显优于\(Kruskal\),于是这道题我用了三种方法 \(Kruskal\) 简单易懂,简洁优美 耗时/内存 344ms, 24343KB 代码: #include…

题目描述 Due to a lack of rain, Farmer John wants to build an irrigation system tosend water between his N fields (1 <= N <= 2000).Each field i is described by a distinct point (xi, yi) in the 2D plane, with 0 <= xi, yi <= 1000. The cost of buildi…

洛谷P1879 [USACO06NOV]玉米田Corn Fields \(f[i][j]\) 表示前 \(i\) 行且第 \(i\) 行状态为 \(j\) 的方案总数.\(j\) 的大小为 \(0 \to (1 >> n - 1)\) . 第 \(i\) 行,种植状态为 \(j\) 的方案总数等于所有合法的 \(f[i-1][k]\) 之和. 状态 \(j\) 满足同一行内没有相邻的两块草地(没有共同边). 状态 \(j\) 和 \(k\) 满足相邻两行的种植情况没有两块草地有共同边. \[…

一道最小生成树模板题,这里用的Kruskal算法,把每两点就加一条边,跑一遍最小生成树即可. #include <bits/stdc++.h> using namespace std; struct node{ int l , r , w; }; node e[4000010]; int n , maxx , tot , now , ans; int fa[2010] , a[2010] , b[2010]; int find(int x){ if(x == fa[x]) return x;…

P1550 [USACO08OCT]打井Watering Hole 题目背景 John的农场缺水了!!! 题目描述 Farmer John has decided to bring water to his N (1 <= N <= 300) pastures which are conveniently numbered 1..N. He may bring water to a pasture either by building a well in that pasture or con…