费用流模板

#include<bits/stdc++.h>
using namespace std;
const int inf=1e9;
const int N=100,M=1000;
struct node{
    int to,rest,next,cost;
}e[M];
int head[N],cnt=1;
inline void addedge(int x,int y,int z,int c){
    e[++cnt].to=y; e[cnt].rest=z; e[cnt].cost= c; e[cnt].next=head[x];
    e[++cnt].to=x; e[cnt].rest=0; e[cnt].cost=-c; e[cnt].next=head[y];
}
int n,m,S,T;
int dis[N],pre[N];
bool vis[N];
int maxflow,mincost;
inline bool SPFA(){
    static queue<int> Q;
    for(int i=S;i<=T;i++) dis[i]=inf,vis[i]=false;
    Q.push(S); dis[S]=0; vis[S]=true;
    while(!Q.empty()){
        int x=Q.front(); Q.pop();
        vis[x]=false;
        for(int i=head[x];i;i=e[i].next){
            int y=e[i].to;
            if(e[i].rest&&dis[y]>dis[x]+e[i].cost){
                dis[y]=dis[x]+e[i].cost;
                pre[y]=i;
                if(vis[y]=false){
                    vis[y]=true;
                    Q.push(y);
                }
            }
        }
    }
    return dis[T]<inf;
}
inline void update(){
    int flow=inf;
    for(int i=pre[T];i;i=pre[e[i^1].to])
        flow=min(flow,e[i].rest);
    for(int i=pre[T];i;i=pre[e[i^1]].to){
        e[i].rest-=flow;
        e[i^1].rest+=flow;
    }
    maxflow+=flow; mincost+=flow*dis[T];
}
inline void MCF(){
    maxflow=mincost=0;
    while(SPFA()) update();
    printf("%d %d",maxflow,mincost);
}
int main(){
    scanf("%d%d",&n,&m);
    S=1; T=n;
    for(int i=1,u,v,z,c;i<=m;i++){
        scanf("%d%d%d%",&u,&v,&z,&c);
        addedge(u,v,z,c);
    }
    MCF();
    return 0;
}