摘要："BZOJ" 题意:给定一个$N$个点$M$条边的有向无环图,如果想要使得原图任意两点的连通性保持不变，最多能删掉多少条边?$Nv$的路径. 对于有向无环图,需要想到拓扑排序,算是一个看到有向无环图的思路之一. 拓扑排序时给每个节点$i$记录一个访问时间$num[i]=tim$,然后把每个节点的出边 阅读全文

摘要："洛咕" 给定一张$n$个点$m$条边的无向图,求两对点($s_1,t_1,s_2,t_2$)间最短路的最长公共路径.$nv$的有向边,$bj[i]$标记第i条边是否在最短路的公共路径上. cpp include include include include include include inc 阅读全文

摘要："洛咕" 题意:有n个点,m条无向边(权值非负),k条有向边(权值可能为负数),给定起点s,求出s点到每个点的最短路径长度.$n include include include include include include include define ll long long using nam 阅读全文

摘要："洛咕" 题意:给定$m$个有序对$(a,b)$,构造一个$n$的排列,满足$m$个有序对中$a$均排在$b$的前面,且1尽量靠前,在1尽量靠前的前提下,2尽量靠前,....以此类推.$n,m include include include include include include inclu 阅读全文

摘要："AcWing" 题意：给定一张N个点M条边的有向无环图，分别统计从每个点出发能够到达的点的数量.$(N,M include include include include include include include using namespace std; inline int read(){ 阅读全文