poj 1753 Flip Game(暴力枚举)

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstdlib>
 4 #include<cstring>
 5 #include<algorithm>
 6 #include<cmath>
 7 #include<queue>
 8 #include<list>
 9 #include<vector>
10 #include<stack>
11 #include<string>
12 #include<map>
13 #include<numeric>
14 #include<set>
15 #include<functional>
16 #include<sstream>
17 #include<time.h>
18 using namespace std;
19 int mapp[4][4];
20 int turn1[5]={1,-1,0,0,0};
21 int turn2[5]={0,0,0,1,-1};
22 const int inf = 0x3f3f3f3f;
23 int ans=inf;
24 
25 int judge( void )    //判断棋盘是否全为0，或全为1
26 {
27     int temp=mapp[0][0];
28     for(int i = 0; i<4; i++)
29     {
30         for(int j = 0; j<4; j++)
31         {
32             if(temp != mapp[i][j])
33                 return 0;
34         }
35     }
36     return 1;
37 }
38 
39 void turn(int x, int y)
40 {
41     for(int i=0;i<5;i++)
42     {
43         if(x+turn1[i]>=0&&x+turn1[i]<4&&y+turn2[i]>=0&&y+turn2[i]<4)
44             mapp[x+turn1[i]][y+turn2[i]]= !mapp[x+turn1[i]][y+turn2[i]];
45     }
46 }
47 
48 int dfs( int x, int y, int t)
49 {
50     if(judge())
51     {
52         ans=min(ans,t);
53         return 0;
54     }
55     if(x >= 4 || y >= 4)
56         return 0;
57     int nx=(x+1)%4;   //坐标，满4换成第二行
58     int ny=y+(x+1)/4;
59     
60     dfs(nx,ny,t);       //搜索翻转
61     turn(x,y);
62     dfs(nx,ny,t+1);
63     turn(x,y);
64     
65     return 0;
66 }
67 int main()
68 {
69     
70     for(int i=0;i<4;i++)
71     {
72         char s[10];
73         gets(s);
74         for(int j=0;j<4;j++)
75         {
76             if(s[j]==‘b‘) mapp[i][j]=1;
77             else mapp[i][j]=0;
78         }
79     }
80     
81     dfs(0,0,0);
82     
83     if(ans!=inf)
84         printf("%d\n",ans);
85     else
86         printf("Impossible\n");
87 }