BZOJ2597 [Wc2007]剪刀石头布（最小费用最大流）

  1 #include<cstdio>
  2 #include<cstring>
  3 #include<queue>
  4 #include<algorithm>
  5 using namespace std;
  6 #define INF (1<<30)
  7 #define MAXN 11111
  8 #define MAXM 111111*4
  9 struct Edge{
 10     int u,v,cap,cost,next;
 11 }edge[MAXM];
 12 int vs,vt,NV,NE,head[MAXN];
 13 void addEdge(int u,int v,int cap,int cost){
 14     edge[NE].u=u; edge[NE].v=v; edge[NE].cap=cap; edge[NE].cost=cost;
 15     edge[NE].next=head[u]; head[u]=NE++;
 16     edge[NE].u=v; edge[NE].v=u; edge[NE].cap=0; edge[NE].cost=-cost;
 17     edge[NE].next=head[v]; head[v]=NE++;
 18 }
 19 int d[MAXN],pre[MAXN];
 20 bool vis[MAXN];
 21 bool SPFA(){
 22     for(int i=0; i<NV; ++i){
 23         d[i]=INF; vis[i]=0;
 24     }
 25     d[vs]=0; vis[vs]=0;
 26     queue<int> que;
 27     que.push(vs);
 28     while(!que.empty()){
 29         int u=que.front(); que.pop();
 30         for(int i=head[u]; i!=-1; i=edge[i].next){
 31             int v=edge[i].v;
 32             if(edge[i].cap && d[v]>d[u]+edge[i].cost){
 33                 d[v]=d[u]+edge[i].cost;
 34                 pre[v]=i;
 35                 if(!vis[v]){
 36                     vis[v]=1;
 37                     que.push(v);
 38                 }
 39             }
 40         }
 41         vis[u]=0;
 42     }
 43     return d[vt]!=INF;
 44 }
 45 int MCMF(){
 46     int res=0;
 47     while(SPFA()){
 48         int flow=INF,cost=0;
 49         for(int u=vt; u!=vs; u=edge[pre[u]].u){
 50             flow=min(flow,edge[pre[u]].cap);
 51         }
 52         for(int u=vt; u!=vs; u=edge[pre[u]].u){
 53             edge[pre[u]].cap-=flow;
 54             edge[pre[u]^1].cap+=flow;
 55             cost+=flow*edge[pre[u]].cost;
 56         }
 57         res+=cost;
 58     }
 59     return res;
 60 }
 61 int ans[111][111];
 62 int main(){
 63     int n,a;
 64     scanf("%d",&n);
 65     vs=n*n+n; vt=vs+1; NV=vt+1; NE=0;
 66     memset(head,-1,sizeof(head));
 67     for(int i=0; i<n; ++i){
 68         int cost=1;
 69         for(int j=1; j<=n; ++j){
 70             addEdge(n*n+i,vt,1,cost);
 71             cost+=2;
 72         }
 73     }
 74     for(int i=0; i<n; ++i){
 75         for(int j=0; j<n; ++j){
 76             scanf("%d",&a);
 77             if(i>=j) continue;
 78             addEdge(vs,i*n+j,1,0);
 79             if(a==1){
 80                 addEdge(i*n+j,n*n+i,1,0);
 81             }else if(a==0){
 82                 addEdge(i*n+j,n*n+j,1,0);
 83             }else{
 84                 addEdge(i*n+j,n*n+i,1,0);
 85                 addEdge(i*n+j,n*n+j,1,0);
 86             }
 87         }
 88     }
 89     printf("%d\n",n*(n-1)*(n-2)/6-(MCMF()-(n-1)*n/2)/2);
 90     for(int x=0; x<n; ++x){
 91         for(int y=x+1; y<n; ++y){
 92             for(int i=head[x*n+y]; i!=-1; i=edge[i].next){
 93                 if(i&1 || edge[i].cap) continue;
 94                 if(edge[i].v==x+n*n){
 95                     ans[x][y]=1; ans[y][x]=0;
 96                 }else{
 97                     ans[x][y]=0; ans[y][x]=1;
 98                 }
 99             }
100         }
101     }
102     for(int i=0; i<n; ++i){
103         for(int j=0; j<n; ++j) printf("%d ",ans[i][j]);
104         putchar(‘\n‘);
105     }
106     return 0;
107 }