HDU 4280 Island Transport(网络流,最大流) Description In the vast waters far far away, there are many islands. People are living on the islands, and all the transport among the islands relies on the ships. You have a transportation company there. Some route…
题意: 求最大流 思路: \(1e5\)条边,偷了一个超长的\(HLPP\)板子.复杂度\(n^2 \sqrt{m}\).但通常在随机情况下并没有isap快. 板子: template<class T = int> struct HLPP{ const int MAXN = 1e5 + 5; const T INF = 0x3f3f3f3f; struct edge{ int to, rev; T f; }; vector<edge> adj[maxn]; deque<int…
Island Transport Time Limit: 10000ms Memory Limit: 65536KB This problem will be judged on HDU. Original ID: 4280 64-bit integer IO format: %I64d      Java class name: Main In the vast waters far far away, there are many islands. People are living on…
Island Transport Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 6217    Accepted Submission(s): 1965 Problem Description In the vast waters far far away, there are many islands. People are l…
HDU 4280:http://acm.hdu.edu.cn/showproblem.php?pid=4280 题意: 比较裸的最大流题目,就是这是个无向图,并且比较卡时间. 思路: 是这样的,由于是无向图,所以addedge 的反边容量直接设为原始流量.然后还可以优化搜索的方向,bfs可以从t到s跑,dfs可以从s到t跑,这样快. //#pragma GCC optimize(3) //#pragma comment(linker, "/STACK:102400000,102400000&qu…
Island Transport Description In the vast waters far far away, there are many islands. People are living on the islands, and all the transport among the islands relies on the ships. You have a transportation company there. Some routes are opened for p…
转载请注明出处:http://blog.csdn.net/u012860063 题目链接:pid=4280">http://acm.hdu.edu.cn/showproblem.php?pid=4280 Problem Description In the vast waters far far away, there are many islands. People are living on the islands, and all the transport among the is…
题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4280 题意:有n个岛屿,m条无向路,每个路给出最大允许的客流量,求从最西的那个岛屿最多能运用多少乘客到最东的那个岛屿 题解:最大流的裸题.输入记得找到最西和最东的岛屿,以及注意是双向边..这题用的sap. 代码: #include<iostream> #include<cstdio> #include<cstring> #include<cmath> #incl…
本题就是使用Floyd算法求全部路径的最短路径,并且须要保存路径,并且更进一步须要依照字典顺序输出结果. 还是有一定难度的. Floyd有一种非常巧妙的记录数据的方法,大多都是使用这种方法记录数据的. 只是事实上本题数据不是非常大,一般太大的数据也无法使用Floyd,由于效率是O(N^3). 所以事实上也能够使用一般的Floyd算法,然后添加个三维数组记录数据.以下就是这样的做法,0ms过了. #include <stdio.h> #include <vector> using s…
Island Transport Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 13187    Accepted Submission(s): 4156 题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4280 Description: In the vast waters far f…