loj 102 最小费用流

补一发费用流的代码

%%%棒神

 #include<iostream>
 #include<cstdio>
 #include<cstring>
 #include<cstdlib>
 #include<cmath>
 #include<algorithm>
 #include<queue>
 #include<vector>
 #include<map>
 #define ll long long
 #define inf 2139062143
 #define MAXN 420
 using namespace std;
 inline int read()
 {
     int x=,f=;char ch=getchar();
     while(!isdigit(ch)) {if(ch=='-') f=-;ch=getchar();}
     while(isdigit(ch)) x=x*+ch-'',ch=getchar();
     return x*f;
 }
 int n,m,ans;
 struct ZKW
 {
     int fst[MAXN],to[MAXN*],nxt[MAXN*],val[MAXN*],cos[MAXN*],cnt;
     int dis[MAXN],s,t,vis[MAXN];
     ZKW() {ans=,cnt=;}//memset(fst,0xff,sizeof(fst));}
     void add(int u,int v,int w,int c) {nxt[cnt]=fst[u],fst[u]=cnt,to[cnt]=v,val[cnt]=w,cos[cnt++]=c;}
     int spfa()
     {
         memset(dis,,sizeof(dis));
         queue<int> q;
         dis[t]=,vis[t]=;
         q.push(t);
         while(!q.empty())
         {
             int x=q.front();q.pop();vis[x]=;
             for(int i=fst[x];i;i=nxt[i])
                 if(val[i^]&&dis[to[i]]>dis[x]-cos[i])
                 {
                     dis[to[i]]=dis[x]-cos[i];
                     if(!vis[to[i]]) {q.push(to[i]);vis[to[i]]=;}
                 }
         }
         memset(vis,,sizeof(vis));
         return dis[s]!=inf;
     }
     int dfs(int x,int a)
     {
         if(x==t||!a) {ans+=dis[s]*a;return a;}
         if(vis[x])return ;
         vis[x]=;
         int res=,f;
         for(int i=fst[x];i&&a;i=nxt[i])
             if(dis[to[i]]==dis[x]-cos[i]&&(f=dfs(to[i],min(a,val[i]))))
                 res+=f,val[i]-=f,val[i^]+=f,a-=f;
         vis[x]=;
         return res;
     }
     int solve()
     {
         int f=;
         while(spfa()) f+=dfs(s,);
         return f;
     }
 }Z;
 int main()
 {
     n=read(),m=read();int a,b,c,d;
     while(m--)
     {
         a=read(),b=read(),c=read(),d=read();
         Z.add(a,b,c,d);
         Z.add(b,a,,-d);
     }
     Z.s=,Z.t=n;
     printf("%d ",Z.solve());
     printf("%d",ans);
 }