[hdu4801]搜索

 1 #include <iostream>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <cmath>
 5 #include <algorithm>
 6 #include <map>
 7 #include <stack>
 8 #include <string>
 9 #include <ctime>
10 #include <queue>
11 #define mem0(a) memset(a, 0, sizeof(a))
12 #define mem(a, b) memset(a, b, sizeof(a))
13 #define lson l, m, rt << 1
14 #define rson m + 1, r, rt << 1 | 1
15 #define eps 0.0000001
16 #define lowbit(x) ((x) & -(x))
17 #define memc(a, b) memcpy(a, b, sizeof(b))
18 #define x_x(a) ((a) * (a))
19 #define LL long long
20 #define DB double
21 #define pi 3.14159265359
22 #define MD 10000007
23 #define INF (int)1e9
24 #define max(a, b) ((a) > (b)? (a) : (b))
25 using namespace std;
26 int arr[6][12] = {
27         {0, 1, 9, 15, 19, 18, 10, 4, 22, 23, 21, 20}, {4, 10, 18, 19, 15, 9, 1, 0, 20, 21, 23, 22},
28         {1, 3, 7, 13, 17, 19, 21, 23, 9, 8, 14, 15}, {23, 21, 19, 17, 13, 7, 3, 1, 15, 14, 8, 9},
29         {22, 23, 9, 8, 7, 6, 5, 4, 0, 1, 3, 2}, {4, 5, 6, 7, 8, 9, 23, 22, 2, 3, 1, 0},
30 };
31 int arr2[6][4] = {{0, 1, 2, 3}, {4, 5, 10, 11}, {6, 7, 12, 13}, {8, 9, 14, 15}, {16, 17, 18, 19}, {20, 21, 22, 23}};
32 int n, ans;
33 struct Node {
34         int a[24];
35         void inp() {
36                 for(int i = 0; i < 24; i++) {
37                         scanf("%d", a + i);
38                 }
39         }
40 };
41 Node doit(Node state, int arr[])
42 {
43         Node tmp = state;
44         for(int i = 0; i < 8; i++) state.a[arr[i]] = tmp.a[arr[(i + 2) % 8]];//转两格
45         for(int i = 0; i < 4; i++) state.a[arr[i + 8]] = tmp.a[arr[(i + 1) % 4 + 8]];//转一格，这里想都没想写成了走两格，wa了无数次，写搜    索题一定要细心啊
46         return state;
47 }
48 int getAns(Node state)
49 {
50         int ans = 0;
51         for(int i = 0; i < 6; i ++) {
52                 int F = 1;
53                 for(int j = 1; j < 4; j++) {
54                         if(state.a[arr2[i][j]] != state.a[arr2[i][j - 1]]) {
55                                 F = 0;
56                                 break;
57                         }
58                 }
59                 ans += F;
60         }
61         return ans;
62 }
63 
64 void dfs(int k, Node state)
65 {
66         if(k > n) return;
67         for(int i = 0; i < 6; i++) {
68                 Node newState = doit(state, arr[i]);
69                 ans = max(ans, getAns(newState));
70                 dfs(k + 1, newState);
71         }
72 }
73 int main()
74 {
75         //freopen("input.txt", "r", stdin);
76         //freopen("output.txt", "w", stdout);
77         while(cin>> n) {
78                 Node state;
79                 state.inp();
80                 ans = getAns(state);
81                 dfs(1, state);
82                 cout<< ans<< endl;
83         }
84         return 0;
85 }