Dinic最大流 || Luogu P3376 【模板】网络最大流

题面：【模板】网络最大流

代码：

 #include<cstring>
 #include<cstdio>
 #include<iostream>
 #define min(a,b) ((a)<(b)?(a):(b))
 using namespace std;
 inline int rd(){
     int x=,f=;char c=getchar();
     while(c<''||c>''){if(c=='-')f=-; c=getchar();}
     while(c>=''&&c<=''){x=x*+c-''; c=getchar();}
     return f*x;
 }
 const int maxn=(1e4)+,maxm=(1e5)+;
 int num_edge=-,edge_head[maxn],N,M,S,T,w,u,v,Q[maxn<<],f1,f2,Dep[maxn],Cur[maxn];
 struct Edge{int to,nx,dis;}edge[maxm<<];
 inline void Add_edge(int from,int to,int dis){
     edge[++num_edge].nx=edge_head[from];
     edge[num_edge].to=to;
     edge[num_edge].dis=dis;
     edge_head[from]=num_edge;
     return;
 }
 inline bool Bfs(){
     memset(Dep,,sizeof(Dep));
     Dep[S]=;
     f1=f2=;
     Q[f2++]=S;
     while(f1<f2){
         int x=Q[f1++];
         for(int i=edge_head[x];i!=-;i=edge[i].nx){
             int y=edge[i].to;
             if(edge[i].dis&&Dep[y]==){
                 Dep[y]=Dep[x]+;
                 Q[f2++]=y;
             }
         }
     }
     if(Dep[T])return ;
     return ;
 }
 inline int Dfs(int x,int fw){
     if(x==T)return fw;
     for(int &i=Cur[x];i!=-;i=edge[i].nx){
         int y=edge[i].to;
         if(Dep[y]==Dep[x]+&&edge[i].dis){
             int p=Dfs(y,min(fw,edge[i].dis));
             if(p>){
                 edge[i].dis-=p;
                 edge[i^].dis+=p;
                 return p;
             }
         }
     }
     return ;
 }
 inline int Dinic(){
     int ans=;
     while(Bfs()){
         for(int i=;i<=N;i++)Cur[i]=edge_head[i];
         while(int k=Dfs(S,<<))ans+=k;
     }
     return ans;
 }
 int main(){
     memset(edge_head,-,sizeof(edge_head));
     N=rd();M=rd();S=rd();T=rd();
     for(int i=;i<=M;i++){
         u=rd();v=rd();w=rd();
         Add_edge(u,v,w);
         Add_edge(v,u,);
     }
     printf("%d\n",Dinic());
     return ;
 }

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By:AlenaNuna