网络流模板

#include<queue>
#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
#define maxn 1000
#define maxm 100000
#define inf 1000000000
#define Clear(a,c) memset(a,c,sizeof(a))

class Costflow
{
	struct Edge
	{
		int u,v,f,cap,cost,n;	
	};
	int h[maxn],d[maxn],pre[maxn];
	int minf,u,v,p,cnt;
	bool vis[maxn];
	Edge e[maxm];
	queue<int> Q;
	public:
	int S,T,flow,cost;;
	Costflow()
	{
		Clear(h,255); cnt=0; flow=0; cost=0;
	}
	void init()
	{
		Clear(h,255); cnt=0; flow=0; cost=0;
	}
	private:
	void add(int u,int v,int cap,int cost)
	{
		e[cnt].u=u; e[cnt].v=v; e[cnt].f=0;
		e[cnt].cap=cap; e[cnt].cost=cost;
		e[cnt].n=h[u]; h[u]=cnt; cnt++;
	}
	bool spfa()
	{
		Clear(vis,0); Clear(pre,255); Clear(d,127);
		Q.push(S); d[S]=0; vis[S]=1;
		while (!Q.empty())
		{
			u=Q.front(); Q.pop(); vis[u]=0;
			for (p=h[u];p>=0;p=e[p].n)
			if (e[p].cap>e[p].f && d[e[p].v]>d[u]+e[p].cost)
			{
				v=e[p].v; d[v]=d[u]+e[p].cost; pre[v]=p;
				if (!vis[v]) Q.push(v),vis[v]=1;
			}
		}
		if (d[T]>inf) return 0;
		else return 1;
	}
	public:
	void addedge(int u,int v,int cap,int cost)
	{
		add(u,v,cap,cost);
		add(v,u,0,-cost);
	}
	void costflow()
	{
		while (spfa())
		{
			minf=inf;
			for (p=pre[T];p>=0;p=pre[e[p].u]) minf=min(minf,e[p].cap-e[p].f);
			for (p=pre[T];p>=0;p=pre[e[p].u]) e[p].f+=minf,e[p^1].f-=minf;
			flow+=minf;
			cost+=minf*d[T];
		}
	}
};

　

#include<queue>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
#define Clear(a,c) memset(a,c,sizeof(a))
#define maxn 50000
#define maxm 1000000
#define inf 1000000000

class Maxflow
{
	private:
	struct Edge
	{
		int v,f,n;
	};
	int g[maxn],vg[maxn],h[maxn];
	int aug,cnt,find;
	Edge e[maxm];
	
	void auge(int u)
	{
		int mgap,taug,v,p;
		mgap=A-1;
		taug=aug;
		if (u==T)
		{
			flow+=aug; find=1;
			return;
		}
		for (p=h[u];p>=0;p=e[p].n)
		if (e[p].f)
		{
			v=e[p].v;
			if (g[u]==g[v]+1)
			{
				aug=min(aug,e[p].f);
				auge(v);
				if (g[S]>=A) return;
				if (find) break;
				aug=taug;
			}
			mgap=min(mgap,g[v]);
		}
		if (find) e[p].f-=aug,e[p^1].f+=aug;
		else
		{
			vg[g[u]]--;
			if (!vg[g[u]]) g[S]=A;
			g[u]=mgap+1;
			vg[g[u]]++;
		}
	}

	public:
	int S,T,A,flow;
	Maxflow()
	{
		Clear(h,255); Clear(g,0); Clear(vg,0); 
		cnt=0; flow=0;
	}
	void init()
	{
		Clear(h,255); Clear(g,0); Clear(vg,0); 
		cnt=0; flow=0;
	}
	void add(int u,int v,int c)
	{
		e[cnt].v=v; e[cnt].f=c; e[cnt].n=h[u]; h[u]=cnt++;
		e[cnt].v=u; e[cnt].f=0; e[cnt].n=h[v]; h[v]=cnt++;
	}
	void maxflow()
	{
		while (g[S]<A)
		{
			aug=inf; find=0; auge(S);
		}
	}
};