洛谷 P2984 [USACO10FEB]给巧克力Chocolate Giving 洛谷传送门 JDOJ 2680: USACO 2010 Feb Silver 2.Chocolate Giving JDOJ传送门 Description Farmer John is distributing chocolates at the barn for Valentine's day, and B (1 <= B <= 25,000) of his bulls have a special cow…

裸最短路.. ------------------------------------------------------------------------------------ #include<cstdio> #include<cstring> #include<algorithm> #include<iostream> #include<queue>   #define rep( i , n ) for( int i = 0 ; i &…

2015: [Usaco2010 Feb]Chocolate Giving Time Limit: 10 Sec  Memory Limit: 162 MBSubmit: 269  Solved: 183[Submit][Status] Description Farmer John有B头奶牛(1<=B<=25000),有N(2*B<=N<=50000)个农场,编号1-N,有M(N-1<=M<=100000)条双向边,第i条边连接农场R_i和S_i(1<=R_i&…

题目描述 Farmer John is distributing chocolates at the barn for Valentine's day, and B (1 <= B <= 25,000) of his bulls have a special cow in mind to receive a chocolate gift. Each of the bulls and cows is grazing alone in one of the farm's N (2*B <=…

https://www.luogu.org/problem/show?pid=2984 题目描述 Farmer John is distributing chocolates at the barn for Valentine's day, and B (1 <= B <= 25,000) of his bulls have a special cow in mind to receive a chocolate gift. Each of the bulls and cows is graz…

Description Farmer John有B头奶牛(1<=B<=25000),有N(2*B<=N<=50000)个农场,编号1-N,有M(N-1<=M<=100000)条双向边,第i条边连接农场R_i和S_i(1<=R_i<=N;1<=S_i<=N),该边的长度是L_i(1<=L_i<=2000).居住在农场P_i的奶牛A(1<=P_i<=N),它想送一份新年礼物给居住在农场Q_i(1<=Q_i<=N)的…

http://www.lydsy.com/JudgeOnline/problem.php?id=2015 这种水题真没啥好说的.. #include <cstdio> #include <cstring> #include <cmath> #include <string> #include <iostream> #include <algorithm> #include <queue> using namespace s…

题目链接:https://www.luogu.org/problemnew/show/P2984 练习SPFA,把FJ当做起点,求出到所有牛的最短路,再把两个牛的相加. #include <cstdio> #include <queue> #include <iostream> #include <algorithm> #include <cstring> using namespace std; ; const int inf = 0x7fff…

因为是双向边,所以相当于两条到1的最短路和,先跑spfa然后直接处理询问即可 #include<iostream> #include<cstdio> #include<queue> using namespace std; const int N=50005,inf=1e9; int n,m,b,h[N],cnt,dis[N]; bool v[N]; struct qwe { int ne,to,va; }e[N<<2]; int read() { int…

题意简叙: FarmerFarmerFarmer JohnJohnJohn有B头奶牛(1<=B<=25000)(1<=B<=25000)(1<=B<=25000),有N(2∗B<=N<=50000)N(2*B<=N<=50000)N(2∗B<=N<=50000)个农场,编号1−N1-N1−N,有M(N−1<=M<=100000)M(N-1<=M<=100000)M(N−1<=M<=100000)条双…