HDU 3567 Eight II

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <climits>
 7 #include <vector>
 8 #include <queue>
 9 #include <cstdlib>
10 #include <string>
11 #include <set>
12 #include <stack>
13 #define LL long long
14 #define pii pair<int,int>
15 #define INF 0x3f3f3f3f
16 using namespace std;
17 const int maxn = 3;
18 struct sta{
19     int x,y;
20     sta(int a = 0,int b = 0){
21         x = a;
22         y = b;
23     }
24 };
25 char mp[maxn][maxn];
26 sta s[11];
27 int nowx,nowy;
28 int h(){
29     int tmp = 0;
30     for(int i = 0; i < 9; i++){
31         int x = i/3,y = i%3;
32         if(mp[x][y] == ‘X‘) continue;
33         tmp += abs(x - s[mp[x][y]-‘0‘].x) + abs(y - s[mp[x][y]-‘0‘].y);
34     }
35     return tmp;
36 }
37 int ans[200],limit;
38 const int dir[4][2] = {1,0,0,-1,0,1,-1,0};
39 const char d[4] = {‘d‘,‘l‘,‘r‘,‘u‘};
40 bool ok;
41 int IDAstar(int x,int y,int p,int cur){
42     int bound = INF,tmp;
43     int hv = h();
44     if(cur + hv > limit) return cur + hv;
45     if(hv == 0) {ok = true;return cur;}
46     for(int i = 0; i < 4; i++){
47         if(i == p) continue;
48         int tx = x + dir[i][0];
49         int ty = y + dir[i][1];
50         if(tx < 0 || tx >= 3 || ty < 0 || ty >= 3) continue;
51         swap(mp[x][y],mp[tx][ty]);
52         ans[cur] = i;
53         int nbound = IDAstar(tx,ty,3-i,cur+1);
54         if(ok) return nbound;
55         bound = min(bound,nbound);
56         swap(mp[x][y],mp[tx][ty]);
57     }
58     return bound;
59 }
60 int main() {
61     int t,cs = 1;
62     char ch;
63     scanf("%d",&t);
64     getchar();
65     while(t--){
66         for(int i = 0; i < 9; i++){
67             ch = getchar();
68             if(ch == ‘X‘){
69                 nowx = i/3;
70                 nowy = i%3;
71             }
72             mp[i/3][i%3] = ch;
73         }
74         getchar();
75         for(int i = 0; i < 9; i++){
76             ch = getchar();
77             if(ch == ‘X‘) continue;
78             s[ch-‘0‘] = sta(i/3,i%3);
79         }
80         getchar();
81         limit = h();
82         ok = false;
83         while(!ok) limit = IDAstar(nowx,nowy,-10,0);
84         printf("Case %d: %d\n",cs++,limit);
85         for(int i = 0; i < limit; i++)
86             putchar(d[ans[i]]);
87         putchar(‘\n‘);
88     }
89     return 0;
90 }