Bzoj1449 [JSOI2009]球队收益

  1 #include<iostream>
  2 #include<cstdio>
  3 #include<algorithm>
  4 #include<cmath>
  5 #include<queue>
  6 #include<cstring>
  7 using namespace std;
  8 const int INF=1e8;
  9 const int mxn=9000;
 10 int read(){
 11     int x=0,f=1;char ch=getchar();
 12     while(ch<‘0‘ || ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
 13     while(ch>=‘0‘ && ch<=‘9‘){x=x*10+ch-‘0‘;ch=getchar();}
 14     return x*f;
 15 }
 16 struct edge{
 17     int from,v,nxt;
 18     int f,w;
 19 }e[mxn<<1];
 20 int hd[mxn],mct=1;//
 21 void add_edge(int u,int v,int c,int w){
 22     e[++mct].v=v;e[mct].from=u;e[mct].nxt=hd[u];e[mct].f=c;e[mct].w=w;hd[u]=mct;return;
 23 }
 24 //
 25 int n,m;
 26 int S,T;
 27 int ans=0;
 28 int win[mxn],lose[mxn],c[mxn],d[mxn];
 29 //
 30 int dis[mxn];
 31 bool inq[mxn];
 32 int pre[mxn<<1];
 33 void SPFA(int s){
 34     memset(dis,0x3f,sizeof dis);
 35     memset(pre,-1,sizeof pre);
 36     queue<int>q;
 37     dis[s]=0;
 38     inq[s]=1;
 39     q.push(s);
 40     while(!q.empty()){
 41         int u=q.front();q.pop();inq[u]=0;
 42         for(int i=hd[u];i;i=e[i].nxt){
 43             if(!e[i].f)continue;
 44             int v=e[i].v;
 45             if(dis[v]>dis[u]+e[i].w){
 46                 dis[v]=dis[u]+e[i].w;
 47                 pre[v]=i;//记录前驱边 
 48                 if(!inq[v]){
 49                     inq[v]=1;
 50                     q.push(v);
 51                 }
 52             }
 53         }
 54     }
 55     return;
 56 }
 57 void maxflow(int s,int t){
 58     SPFA(s);
 59     while(pre[t]!=-1){
 60         int tmp=INF;
 61         for(int i=pre[t];i!=-1;i=pre[e[i].from])
 62             tmp=min(tmp,e[i].f);
 63         ans+=dis[t]*tmp;
 64         for(int i=pre[t];i!=-1;i=pre[e[i].from]){
 65             e[i].f-=tmp;
 66             e[i^1].f+=tmp;
 67         }
 68         SPFA(s);
 69     }
 70     return;
 71 }
 72 int a[mxn],b[mxn];
 73 int main()
 74 {
 75     int i,j,u,v;
 76     n=read();m=read();
 77     for(i=1;i<=n;i++){
 78         win[i]=read();lose[i]=read();
 79         c[i]=read();d[i]=read();
 80     }
 81     for(i=1;i<=m;i++){
 82         a[i]=read();b[i]=read();
 83         ++lose[a[i]];++lose[b[i]];
 84     }
 85     for(i=1;i<=n;i++){//假设全部都输掉 
 86         ans+=c[i]*win[i]*win[i];
 87         ans+=d[i]*lose[i]*lose[i];
 88     }
 89     S=0;T=m+n+2;
 90     for(i=1;i<=m;i++){
 91         add_edge(S,i,1,0);
 92         add_edge(i,S,0,0);
 93         add_edge(i,m+a[i],1,0);
 94         add_edge(m+a[i],i,0,0);
 95         add_edge(i,m+b[i],1,0);
 96         add_edge(m+b[i],i,0,0);
 97         //a
 98         int cost=c[a[i]]*(2*win[a[i]]+1)-d[a[i]]*(2*lose[a[i]]-1);
 99         add_edge(m+a[i],T,1,cost);
100         add_edge(T,m+a[i],0,-cost);
101         win[a[i]]++;lose[a[i]]--;
102         //b
103         cost=c[b[i]]*(2*win[b[i]]+1)-d[b[i]]*(2*lose[b[i]]-1);
104         add_edge(m+b[i],T,1,cost);
105         add_edge(T,m+b[i],0,-cost);
106         win[b[i]]++;lose[b[i]]--;
107     }
108     maxflow(S,T);
109     printf("%d\n",ans);
110     return 0;
111 }