HDU 4738 Caocao ' s Bridges (bridge min weight + de-weight)

http://acm.hdu.edu.cn/showproblem.php?pid=4738

The main idea of the main topic: there are some islands are connected by the bridge, each seat is guarded by soldiers, Zhou Yu wanted to divide the islands into two parts, but he can only blow up a bridge, asked to send a few soldiers to go; If you cannot complete output-1

1: If these islands are not connected, you do not need to send people to

2: If the bridge's guard is 0, you'll have to send a man to blow it up.

3: If output cannot be completed-1

4: Output minimum number of people to be sent

#include <stdio.h>#include<string.h>#include<math.h>#include<queue>#include<algorithm>using namespacestd;#defineN 1100#defineINF 0XFFFFFFFintDfn[n], low[n], head[n], f[n];intTime , M, N, Min, CNT;structedge{intNext, U, V, c;} Edge[n*N];voidInit () {memset (head,-1,sizeof(head)); memset (DFN,0,sizeof(DFN)); memset (Low,0,sizeof(low)); Memset (F,0,sizeof(f)); time= CNT =0;}voidAddedge (intUintVintc) {edge[cnt].u=u; EDGE[CNT].V=v; EDGE[CNT].C=C; Edge[cnt].next=Head[u]; Head[u]= cnt++;}voidTarjan (intUintFA) {    intI, V, flag =0; Low[u]= Dfn[u] = + +Time ; F[u]=FA;  for(i = head[u]; I! =-1; i =Edge[i].next) {v=edge[i].v; if(v = = FA &&!)flag) {Flag=1; Continue; }//go to the heavy side and skip if there are heavy edges        if(!Dfn[v])            {Tarjan (V, u); Low[u]=min (Low[u], low[v]); if(Dfn[u] <Low[v]) Min=min (min, edge[i].c); }        ElseLow[u]=min (Low[u], dfn[v]); }}intMain () {inti, U, V, c, K;  while(SCANF ("%d%d", &m, &n), M +N) {Init (); K=0;  while(n--) {scanf ("%d%d%d", &u, &v, &c);            Addedge (U, V, c);        Addedge (V, U, c); } Min=INF;  for(i =1; I <= m; i++)        {            if(!Dfn[i]) {Tarjan (i,-1); K++; }        }        if(k >1) {printf ("0\n"); Continue; }//1        if(Min = =0) printf ("1\n");//2        Else if(Min = =INF) printf ("-1\n");//3        Elseprintf ("%d\n", Min);//4    }    return 0;}

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HDU 4738 Caocao ' s Bridges (bridge min weight + de-weight)