hdu 3061 最大权闭合子图

属于模板题吧。。。

 #include <cstdio>
 #include <cstring>
 #include <vector>
 #define min(a,b) ((a)<(b)?(a):(b))
 #define oo 0x3f3f3f3f
 #define N 610
 using namespace std;

 struct Edge {
     int u, v, f;
     Edge( int u, int v, int f ):u(u),v(v),f(f){}
 };
 struct Dinic {
     int src, dst;
     vector<Edge> edge;
     vector<int> g[N];
     int dep[N], cur[N], qu[N], bg, ed;

     void init( int n, int src, int dst ) {
         this->src = src;
         this->dst = dst;
         for( int i=; i<=n; i++ )
             g[i].clear();
         edge.clear();
     }
     void adde( int u, int v, int f ) {
         g[u].push_back( edge.size() );
         edge.push_back( Edge(u,v,f) );
         g[v].push_back( edge.size() );
         edge.push_back( Edge(v,u,) );
     }
     bool bfs() {
         memset( dep, , sizeof(dep) );
         qu[bg=ed=] = src;
         dep[src] = ;
         while( bg<=ed ) {
             int u=qu[bg++];
             for( int t=; t<g[u].size(); t++ ) {
                 Edge &e = edge[g[u][t]];
                 if( e.f && !dep[e.v] ) {
                     dep[e.v] = dep[e.u]+;
                     qu[++ed] = e.v;
                 }
             }
         }
         return dep[dst];
     }
     int dfs( int u, int a ) {
         if( u==dst || a== ) return a;
         int remain=a, past=, na;
         for( int &t=cur[u]; t<g[u].size(); t++ ) {
             Edge &e = edge[g[u][t]];
             Edge &ve = edge[g[u][t]^];
             if( e.f && dep[e.v]==dep[e.u]+ && (na=dfs(e.v,min(remain,e.f))) ) {
                 remain -= na;
                 past += na;
                 e.f -= na;
                 ve.f += na;
                 if( !remain ) break;
             }
         }
         return past;
     }
     int maxflow() {
         int flow = ;
         while( bfs() ) {
             memset( cur, , sizeof(cur) );
             flow += dfs(src,oo);
         }
         return flow;
     }
 }D;

 int n, m;
 int src, dst;
 int wght[N], sum;

 int main() {
     while( scanf("%d%d",&n,&m)== ) {
         src = n+, dst = n+;
         D.init( n+, src, dst );
         sum = ;
         for( int i=; i<=n; i++ ) {
             scanf( "%d", wght+i );
             if( wght[i]> )
                 D.adde( src, i, wght[i] ), sum += wght[i];
             if( wght[i]< )
                 D.adde( i, dst, -wght[i] );
         }
         for( int i=,u,v; i<=m; i++ ) {
             scanf( "%d%d", &u, &v );
             D.adde( u, v, oo );
         }
         printf( "%d\n", sum - D.maxflow() );
     }
 }