Zoj 3792 Romantic Value

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The minimum cut value, and the number of edges with the least cutting edge.

First, the minimum cut, and then the weight of all the cutting edge into 1, the other side into the INF, in the minimum cut, at this time to find the minimum number of sides.

INF to the INF WA a few rounds ......

1#include <bits/stdc++.h>2 using namespacestd;3 #definePB (x) push_back (x)4 #definell Long Long5 #defineMK (x, y) make_pair (x, y)6 #defineLson L, M, rt<<17 #defineMem (a) memset (a, 0, sizeof (a))8 #defineRson m+1, R, rt<<1|19 #defineMem1 (a) memset (a,-1, sizeof (a))Ten #defineMEM2 (a) memset (a, 0x3f, sizeof (a)) One #defineRep (I, A, n) for (int i = A; i<n; i++) A #defineull unsigned long Long -typedef pair<int,int>PLL; - Const DoublePI = ACOs (-1.0); the Const DoubleEPS = 1e-8; - Const intMoD = 1e9+7; - Const intINF =1e4; - Const intdir[][2] = { {-1,0}, {1,0}, {0, -1}, {0,1} }; + Const intMAXN = 2e5+5; - intNum, q[maxn*5], head[maxn*2], dis[maxn*2], S, t; + structnode A { at     intto, Nextt, C; - node () {} -NodeintTo,intNextt,intc): To, Nextt (NEXTT), C (c) {} -}e[maxn*2]; - intBFs () { - mem (dis); in     intSt =0, ed =0; -Dis[s] =1; toq[ed++] =s; +      while(st<ed) { -         intU = q[st++]; the          for(inti = Head[u]; ~i; i =e[i].nextt) { *             intv =e[i].to; $             if(!dis[v]&&e[i].c) {Panax NotoginsengDIS[V] = dis[u]+1; -                 if(v = =t) the                     return 1; +q[ed++] =v; A             } the         } +     } -     return 0; $ } $ intDfsintUintlimit) { -     intCost =0; -     if(U = =t) the         returnlimit; -      for(inti = Head[u]; ~i; i =e[i].nextt) {Wuyi         intv =e[i].to; the         if(E[i].c&&dis[v] = = dis[u]+1) { -             intTMP = DFS (V, min (e[i].c, limit-Cost )); Wu             if(tmp>0) { -E[I].C-=tmp; Aboute[i^1].C + =tmp; $Cost + =tmp; -                 if(Cost = =limit) -                      Break; -}Else { ADIS[V] =-1; +             } the         } -     } $     returnCost ; the } the intDinic () { the     intAns =0; the      while(BFS ()) { -Ans + =DFS (s, INF); in     } the     returnans; the } About voidAddintUintVintc) { theE[num] = node (V, Head[u], c); Head[u] = num++; theE[num] = node (u, head[v], c); HEAD[V] = num++; the } + voidinit () { - mem1 (head); thenum =0;Bayi } the intMain () the { -     intT, M, n, x, y, q, p, Z; -Cin>>T; the      while(t--) { the init (); the         intsum =0; thescanf"%d%d%d%d", &n, &m, &p, &q); -s = p, t =Q; the          while(m--) { thescanf"%d%d%d", &x, &y, &z); the Add (x, y, z);94Sum + =Z; the         } the         intAns =dinic (); the         if(ans = =0) {98cout<<"INF"<<Endl; About             Continue; -         }101Sum-=ans;102          for(inti =0; i<num; i+=2) {103             if(E[I].C = =0) {104E[I].C =1; thee[i^1].C =inf;106}Else if(e[i^1].c==0) {107E[I].C =inf;108e[i^1].C =1;109}Else { theE[I].C = e[i^1].C =inf;111             } the         }113Ans =dinic (); theprintf"%.2f\n",1.0*sum/ans); the     } the}

Zoj 3792 Romantic Value