（IDA*）POJ 2286 The Rotation Game

  1 #include <iostream>
  2 #include <string>
  3 #include <algorithm>
  4 #include <cstring>
  5 #include <cstdio>
  6 #include <cmath>
  7 #include <queue>
  8 #include <set>
  9 #include <map>
 10 #include <list>
 11 #include <vector>
 12 #include <stack>
 13 #define mp make_pair
 14 //#define P make_pair
 15 #define MIN(a,b) (a>b?b:a)
 16 //#define MAX(a,b) (a>b?a:b)
 17 typedef long long ll;
 18 typedef unsigned long long ull;
 19 const int MAX=1e2+5;
 20 const int INF=1e8+5;
 21 using namespace std;
 22 //const int MOD=1e9+7;
 23 typedef pair<ll,int> pii;
 24 const double eps=0.00000001;
 25 int a[30];
 26 bool st=false;
 27 int rot[9][8]={{},{1,3,7,12,16,21,23},{2,4,9,13,18,22,24},{11,10,9,8,7,6,5},{20,19,18,17,16,15,14},
 28             {14,15,16,17,18,19,20},{5,6,7,8,9,10,11},{24,22,18,13,9,4,2},{23,21,16,12,7,3,1}};
 29 int cen[10]={7,8,9,12,13,16,17,18};
 30 int num[4];
 31 char re[10]={‘A‘,‘A‘,‘B‘,‘C‘,‘D‘,‘G‘,‘H‘,‘E‘,‘F‘};
 32 int aim;
 33 int se[10]={0,1,2,3,4,7,8,5,6};
 34 string ans;
 35 int check()//返回估值
 36 {
 37     memset(num,0,sizeof(num));
 38     for(int i=0;i<8;i++)
 39     {
 40         ++num[a[cen[i]]];
 41     }
 42     int re=max(max(num[1],num[2]),num[3]);
 43     for(int i=1;i<=3;i++)
 44         if(num[i]==re)
 45             aim=i;
 46     return 8-re;
 47 }
 48 void change(int i)
 49 {
 50     int tem=a[rot[i][0]];
 51     for(int j=0;j<6;j++)
 52         a[rot[i][j]]=a[rot[i][j+1]];
 53     a[rot[i][6]]=tem;
 54 }
 55 void dfs(int last,int step,int limit)//9-last操作即为反过来的操作
 56 {
 57     int tem=check();
 58     if(tem==0)
 59     {
 60         st=true;
 61         if(last)
 62             ans+=re[last];
 63         return;
 64     }
 65     if(step+tem>limit)
 66         return;
 67     for(int i=1;i<=8;i++)
 68     {
 69         if(se[i]==9-last)
 70             continue;
 71         change(se[i]);
 72         dfs(se[i],step+1,limit);
 73         if(st)
 74         {
 75             if(last)
 76                 ans+=re[last];
 77             return;
 78         }
 79         change(9-se[i]);
 80     }
 81 }
 82 int main()
 83 {
 84     while(scanf("%d",&a[1])&&a[1])
 85     {
 86         for(int i=2;i<=24;i++)
 87             scanf("%d",&a[i]);
 88         ans="";
 89         st=false;
 90         for(int i=0;!st;i++)
 91         {
 92             dfs(0,0,i);
 93         }
 94         reverse(ans.begin(),ans.end());
 95         if(ans.size())
 96             cout<<ans<<"\n";
 97         else
 98             printf("No moves needed\n");
 99         printf("%d\n",aim);
100     }
101 }