delete pics to save space

1.3376.cpp

@@ -0,0 +1,154 @@
+#include<cstdio>
+#include<cstring>
+#include<vector>
+#include<queue>
+#include<algorithm> 
+using namespace std;
+const int oo=1e9+7;
+const int maxn=10005;
+const int maxm=100005;
+namespace HLPP
+{
+	struct Edge { int v,cap,next; };
+	int n,s,t;
+	int h[maxn],cnt[maxn],prs[maxn];
+	struct cmp { inline bool operator()(int a,int b) { return h[a]<h[b]; } };
+	Edge e[maxm*2]; int G[maxn],ecnt=1;
+	priority_queue<int,vector<int>,cmp> Q;
+	inline void AddEdge(int from,int to,int cap)
+	{
+		e[++ecnt]=(Edge){to,cap,G[from]}; G[from]=ecnt;
+		e[++ecnt]=(Edge){from,0,G[to]}; G[to]=ecnt;
+	}
+	inline bool push(int u,int v,int p)
+	{
+		int flow=min(prs[u],e[p].cap);
+		e[p].cap-=flow; e[p^1].cap+=flow;
+		prs[u]-=flow; prs[v]+=flow;
+		return flow;
+	}
+	inline void Gap(int l)
+	{ for(int i=1;i<=n;i++) if(i!=s&&i!=t&&l<h[i]&&h[i]<=n) h[i]=n+1;  }
+	int Maxflow(int n,int s,int t)
+	{
+		HLPP::s=s; HLPP::t=t; HLPP::n=n;
+		h[s]=n; prs[s]=oo; Q.push(s);
+		while(Q.size())
+		{
+			int u=Q.top(); Q.pop();
+			if(!prs[u]) continue;
+			for(int i=G[u],v=e[i].v;i;i=e[i].next,v=e[i].v)
+				if((u==s||h[u]==h[v]+1)&&push(u,v,i)&&v!=t&&v!=s)
+					Q.push(v);
+			if(u!=s&&prs[u])
+			{
+				if(!(--cnt[h[u]])) Gap(h[u]);
+				++cnt[++h[u]]; Q.push(u);
+			}
+		}
+		return prs[t];
+	}
+}
+int n,m,s,t,u,v,w;
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d%d%d%d",&n,&m,&s,&t);
+	while(m-->0)
+	{
+		scanf("%d%d%d",&u,&v,&w);
+		HLPP::AddEdge(u,v,w);
+	}
+	printf("%d\n",HLPP::Maxflow(n,s,t));
+	return 0;
+}
+//#include<cstdio>
+//#include<cstring>
+//#include<vector>
+//#include<queue>
+//#include<algorithm> 
+//using namespace std;
+//const int oo=1e9+7;
+//const int maxn=10005;
+//struct Edge { int from,to,cap,flow; };
+//struct Dinic
+//{
+//	int n,m,s,t;
+//	vector<Edge> edges;
+//	vector<int> G[maxn];
+//	bool vis[maxn];
+//	int d[maxn],pos[maxn];
+//	inline void AddEdge(int from,int to,int cap)
+//	{
+//		edges.push_back((Edge){from,to,cap,0});
+//		edges.push_back((Edge){to,from,0,0});
+//		m=edges.size();
+//		G[from].push_back(m-2);
+//		G[to].push_back(m-1);
+//	}
+//	inline bool BFS()
+//	{
+//		memset(vis,0,sizeof(vis));
+//		queue<int> Q;
+//		Q.push(s); vis[s]=true; d[s]=0;
+//		while(Q.size())
+//		{
+//			int u=Q.front(); Q.pop();
+//			for(int i=0;i<G[u].size();i++)
+//			{
+//				Edge &e=edges[G[u][i]];
+//				if(!vis[e.to]&&e.cap>e.flow)
+//				{
+//					vis[e.to]=true;
+//					d[e.to]=d[u]+1;
+//					Q.push(e.to);
+//				}
+//			}
+//		}
+//		return vis[t];
+//	}
+//	inline int DFS(int u,int a)
+//	{
+//		if(u==t||a==0) return a;
+//		int flow=0,f;
+//		for(int &i=pos[u];i<G[u].size();i++)
+//		{
+//			Edge &e=edges[G[u][i]];
+//			if(d[u]+1==d[e.to]&&(f=DFS(e.to,min(a,e.cap-e.flow)))>0)
+//			{
+//				e.flow+=f; flow+=f;
+//				edges[G[u][i]^1].flow-=f; a-=f;
+//				if(a==0) break;
+//			}
+//		}
+//		return flow;
+//	}
+//	int Maxflow(int s,int t)
+//	{
+//		this->s=s; this->t=t;
+//		int flow=0;
+//		while(BFS())
+//		{
+//			memset(pos,0,sizeof(pos));
+//			flow+=DFS(s,oo);
+//		}
+//		return flow;
+//	}
+//}dinic;
+//int n,m,s,t,u,v,w;
+//int main()
+//{
+//#ifdef local
+//	freopen("pro.in","r",stdin);
+//#endif
+//	scanf("%d%d%d%d",&n,&m,&s,&t);
+//	while(m-->0)
+//	{
+//		scanf("%d%d%d",&u,&v,&w);
+//		dinic.AddEdge(u,v,w);
+//	}
+//	printf("%d\n",dinic.Maxflow(s,t));
+//	return 0;
+//}