洛谷P3381 【模板】最小费用最大流(dijstra费用流)

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// luogu-judger-enable-o2
#include<cstdio>
#include<cstring>
#include<queue>
#define Pair pair<int,int>
#define fi first
#define se second
#define AddEdge(x,y,f,z) add_edge(x,y,f,z);add_edge(y,x,0,-z);
#define getchar() (p1==p2&&(p2=(p1=buf)+fread(buf,1,MAXN,stdin),p1==p2)?EOF:*p1++)
char buf[1<<20],*p1=buf,*p2=buf;
using namespace std;
const int MAXN=1e6+1,INF=1e8+10;
inline int read()
{
    char c=getchar();int x=0,f=1;
    while(c<'0'||c>'9'){if(c=='-')f=-1;c=getchar();}
    while(c>='0'&&c<='9'){x=x*10+c-'0';c=getchar();}
    return x*f;
}
int N,M,S,T;
struct node
{
    int u,v,f,w,nxt;
}edge[MAXN];
int head[MAXN],num=2;
inline void add_edge(int x,int y,int f,int z)
{
    edge[num].u=x;
    edge[num].v=y;
    edge[num].f=f;
    edge[num].w=z;
    edge[num].nxt=head[x];
    head[x]=num++;
}
int h[MAXN],dis[MAXN],PrePoint[MAXN],PreEdge[MAXN];
Pair Dij()
{
    int ansflow=0,anscost=0;
    while(1)
    {
        priority_queue<Pair>q;
        memset(dis,0xf,sizeof(dis));
        dis[S]=0;
        q.push(make_pair(0,S));
        while(q.size()!=0)
        {
            Pair p=q.top();q.pop();
            if(-p.fi!=dis[p.se]) continue;
            if(p.se==T) break;
            for(int i=head[p.se];i!=-1;i=edge[i].nxt)
            {
                int nowcost=edge[i].w+h[p.se]-h[edge[i].v];
                if(edge[i].f>0&&dis[edge[i].v]>dis[p.se]+nowcost)
                {
                    dis[edge[i].v]=dis[p.se]+nowcost;
                    q.push(make_pair(-dis[edge[i].v],edge[i].v));
                    PrePoint[edge[i].v]=p.se;
                    PreEdge[edge[i].v]=i;
                }
            }
        }
        if(dis[T]>INF) break;
        for(int i=0;i<=N;i++) h[i]+=dis[i];
        int nowflow=INF;
        for(int now=T;now!=S;now=PrePoint[now])
            nowflow=min(nowflow,edge[PreEdge[now]].f);
        for(int now=T;now!=S;now=PrePoint[now])
            edge[PreEdge[now]].f-=nowflow,
            edge[PreEdge[now]^1].f+=nowflow;
        ansflow+=nowflow;
        anscost+=nowflow*h[T];
    }
    return make_pair(ansflow,anscost);
}
int main()
{
    #ifdef WIN32
    freopen("a.in","r",stdin);
    #endif
    memset(head,-1,sizeof(head));
    N=read(),M=read(),S=read(),T=read();
    for(int i=1;i<=M;i++)
    {
        int x=read(),y=read(),f=read(),z=read();
        AddEdge(x,y,f,z);
    }
    Pair ans=Dij();
    printf("%d %d",ans.fi,ans.se);
    return 0;
}