POJ3068 "Shortest" pair of paths Description A chemical company has an unusual shortest path problem. There are N depots (vertices) where chemicals can be stored. There are M individual shipping methods (edges) connecting pairs of depots. Each i…

嘟嘟嘟 题目大意:一个有向图,每一条边有一个边权,求从节点\(0\)到\(n - 1\)的两条不经过同一条边的路径,并且边权和最小. 费用流板子题. 发个博客证明一下我写了这题. #include<cstdio> #include<iostream> #include<cmath> #include<algorithm> #include<cstring> #include<cstdlib> #include<cctype>…

题解: 最小费用最大流 每一次找最短的 代码: #include<cstdio> #include<cmath> #include<cstring> #include<algorithm> #include<queue> using namespace std; ; int fi[N],n,t,cas,m,x,y,z,f[N],ne[N],num,zz[N],fl[N],gp[N],dist[N],pre[N],sl[N]; void jb(in…

http://poj.org/problem?id=3068 题目大意: 从0-n-1找到两条边和点都不相同(除了0和n-1外)的最小费用路径. ———————————————————————————— POJ2135魔改版. 按照那题的思路并且把点拆成中间连一条容量为1的边即可. 切了切了. #include<cstdio> #include<iostream> #include<queue> #include<cstring> #include<a…