P2762 [网络流24题]太空飞行计划问题(最小割)

地址

最大权闭合子图裸题，不说了吧，求方案就是把s集遍历一遍。

错误记录：dfs那块忘判断残量了，11分×1.

 1 #include<cstdio>
 2 #include<iostream>
 3 #include<cstring>
 4 #include<queue>
 5 using namespace std;
 6 typedef long long ll;
 7 template<typename T>inline char MIN(T&A,T B){return A>B?A=B,1:0;}
 8 template<typename T>inline char MAX(T&A,T B){return A<B?A=B,1:0;}
 9 template<typename T>inline T _min(T A,T B){return A<B?A:B;}
10 template<typename T>inline T _max(T A,T B){return A>B?A:B;}
11 template<typename T>inline void inc(T&A,T B){A+=B;}
12 inline int read(int&x){
13     x=0;int f=0;char c;while(!isdigit(c=getchar()))if(c=='-')f=1;
14     while(isdigit(c))x=x*10+c-'0',c=getchar();if(c=='\n')return -1;return f?-x:x;
15 }
16 const int N=100+7,M=10000+7,INF=0x3f3f3f3f;
17 int Head[N],cur[N],Next[M<<1],v[M<<1],w[M<<1],dis[N],vis[N],tot=1,n,m,cnt,s,t;
18 
19 inline void Addedge(int x,int y,int z){
20     v[++tot]=y,Next[tot]=Head[x],Head[x]=tot,w[tot]=z;
21     v[++tot]=x,Next[tot]=Head[y],Head[y]=tot,w[tot]=0;
22 }
23 #define y v[j]
24 inline int bfs(){
25     queue<int> q;memset(dis,0,sizeof dis),dis[s]=1,q.push(s);
26     for(register int i=1;i<=(n+m)+2;++i)cur[i]=Head[i];
27     while(!q.empty()){
28         int x=q.front();q.pop();
29         for(register int j=Head[x];j;j=Next[j])if(w[j]&&!dis[y]){
30             dis[y]=dis[x]+1,q.push(y);
31             if(y==t)return 1;
32         }
33     }
34     return 0;
35 }
36 int dinic(int x,int flow){
37     if(!flow||x==t)return flow;
38     int rest=flow,k;
39     for(register int j=cur[x];j&&rest;cur[x]=j,j=Next[j])if(w[j]&&dis[y]==dis[x]+1){
40         if(!(k=dinic(y,_min(rest,w[j]))))dis[y]=0;
41         rest-=k,w[j]-=k,w[j^1]+=k;
42     }
43     return flow-rest;
44 }
45 #undef y
46 int x,y,z,maxflow;ll ans;
47 void dfs(int x){
48     vis[x]=1;for(register int j=Head[x];j;j=Next[j])if(w[j]&&!vis[v[j]])dfs(v[j]); 
49 }
50 
51 int main(){//freopen("P2762.in","r",stdin);//freopen("tmp.out","w",stdout);
52     read(m),read(n);s=n+m+1,t=s+1;
53     for(register int i=1;i<=m;++i){
54         ans+=read(z),Addedge(s,i,z);while(~read(y))Addedge(i,y+m,INF); Addedge(i,y+m,INF);
55     }
56     for(register int i=1;i<=n;++i)read(z),Addedge(i+m,t,z);
57     while(bfs())maxflow+=dinic(s,INF);//printf("%lld %d\n",ans,maxflow);
58     ans-=maxflow,dfs(s);
59     for(register int i=1;i<=m;++i)if(vis[i])printf("%d ",i);puts("");
60     for(register int i=1;i<=n;++i)if(vis[i+m])printf("%d ",i);puts("");
61     printf("%d\n",ans);
62     return 0;
63 }

标签：24,templateinline,return,int,char,P2762,include,太空飞行,dis
来源： https://www.cnblogs.com/saigyouji-yuyuko/p/10361442.html