网络流模板--zhengjun

#include<bits/stdc++.h>
using namespace std;
using ll=long long;
const int N=1e5+10,M=2e5+10,Inf=1e9;
namespace Flow{
	const ll INF=1e18;
	const int V=N,E=M*2+N*2*2;
	int s,t,kk,head[V],cur[V],vis[V];
	ll d[V];
	struct edges{
		int to,c,w,nex;
	}edge[E];
	void init(int x,int y){
		s=x,t=y,kk=1;
		fill(head+s,head+1+t,0);
	}
	void add(int u,int v,int c,int w){
		edge[++kk]={v,c,w,head[u]},head[u]=kk;
		edge[++kk]={u,0,-w,head[v]},head[v]=kk;
	}
	bool bfs(){
		queue<int>q;
		copy(head+s,head+1+t,cur+s);
		fill(d+s,d+1+t,INF),d[s]=0;
		q.push(s);
		for(int u;!q.empty();){
			u=q.front(),q.pop();
			for(int i=head[u];i;i=edge[i].nex){
				int v=edge[i].to,c=edge[i].c,w=edge[i].w;
				if(c&&d[v]>d[u]+w){
					d[v]=d[u]+w,q.push(v);
				}
			}
		}
		return d[t]<INF;
	}
	ll sum;
	int dfs(int u,int lim=Inf){
		if(u==t)return lim;
		vis[u]=1;
		int flow=0;
		for(int i=cur[u];i&&flow<lim;i=edge[i].nex){
			cur[u]=i;
			int v=edge[i].to,c=edge[i].c;
			if(!c||d[v]!=d[u]+edge[i].w||vis[v])continue;
			int f=dfs(v,min(lim-flow,edge[i].c));
			if(!f)d[v]=INF;
			edge[i].c-=f,edge[i^1].c+=f,flow+=f;
			sum+=1ll*f*edge[i].w;
		}
		vis[u]=0;
		return flow;
	}
	int dinic(){
		int flow=0;
		for(;bfs();)flow+=dfs(s);
		return flow;
	}
}
int main(){
	return 0;
}