hdu 4753 Fishhead’s Little Game 博弈论+记忆化搜索

思路：状态最多有2^12，采用记忆化搜索！！

代码如下：

 #include<iostream>
 #include<stdio.h>
 #include<algorithm>
 #include<iomanip>
 #include<cmath>
 #include<cstring>
 #include<vector>
 #define inf 1<<30
 using namespace std;
 int edge[][]={{,},{,},{,},{,},{,},{,},{,},{,},{,},{,},{,},
 {,},{,},{,},{,},{,},{,},{,},{,},{,},{,},{,},
 {,},{,}};
 int tri[][]={{,,,},{,,,},{,,,},{,,,},{,,,},
 {,,,},{,,,},{,,,},{,,,}};
 int p[],index[],cnt;
 int dp[<<];
 int cal(int state,int e)
 {
       int ans=,t=;
       for(int i=;i<;i++){
             bool flag=;
             for(int j=;j<;j++)
                   if(e==tri[i][j]){
                         flag=true;
                         break;
                   }
             if(flag){
                   t++;
                   for(int j=;j<;j++){
                         if(!(p[tri[i][j]]&state||e==tri[i][j])){
                               ans--;break;
                         }
                   }
                   ans++;
             }
             if(t==) break;
       }
       return ans;
 }
 int dfs(int state,int now)
 {
       if(dp[now]!=-inf) return dp[now];
       int ans=-inf;
       for(int i=;i<cnt;i++){
             if(!(now&p[i])){
                   int tt=cal(state,index[i]);
                   tt-=dfs(state|p[index[i]],now|p[i]);
                   ans=max(ans,tt);
             }
       }
       return dp[now]=ans;
 }
 int main()
 {
     int t,u,v,ca=,m;
     bool vis[];
     p[]=;
     for(int i=;i<=;i++) p[i]=p[i-]*;
     scanf("%d",&t);
     while(t--){
             scanf("%d",&m);
             int m0=,m1=,tt=,state=,side=;
             memset(vis,,sizeof(vis));
             while(m--){
                   scanf("%d%d",&u,&v);
                   if(u>v) swap(u,v);
                   for(int i=;i<;i++)
                         if(edge[i][]==u&&edge[i][]==v){
                               tt=cal(state,i);
                               vis[i]=;
                               state|=p[i];
                               side==?m0+=tt:m1+=tt;
                               side++;
                               side%=;
                               break;
                         }
             }
             cnt=;
             for(int i=;i<;i++){
                 if(!vis[i]){
                     index[cnt++]=i;
                 }
             }
             for(int i=;i<(<<cnt);i++) dp[i]=-inf;
             dp[(<<cnt)-]=;
             int ans=m0-m1;
             if(side==) ans+=dfs(state,);
             else ans-=dfs(state,);
             printf("Case #%d: %s\n",++ca,ans>?"Tom200":"Jerry404");
     }
     return ;
 }