HDU 1426 Sudoku Killer DFS 简单题

 1 #include<cstdio>
 2 #include<cstring>
 3 int maze[12][12];
 4 int tot;
 5 bool over;
 6 struct Point
 7 {
 8     int x,y;
 9 }point[85];
10 int change(int x)
11 {
12     if(1<=x&&x<=3)
13         return 1;
14     if(4<=x&&x<=6)
15         return 4;
16     if(7<=x&&x<=9)
17         return 7;
18 }
19 bool judge(int cnt,int t)
20 {
21     for(int i=1;i<=9;i++)
22     {
23         if(maze[point[cnt].x][i]==t||maze[i][point[cnt].y]==t)
24             return false;
25     }
26     int u=change(point[cnt].x);
27     int v=change(point[cnt].y);
28     for(int jj=u;jj<=u+2;jj++)
29     {
30         for(int jjj=v;jjj<=v+2;jjj++)
31             if(maze[jj][jjj]==t)
32                 return false;
33     }
34     return true;
35 }
36 void dfs(int cnt)//have been finish the number of cnt
37 {
38     if(cnt==tot)
39     {
40         for(int i=1;i<=9;i++)
41         {
42             for(int j=1;j<9;j++)
43                 printf("%d ",maze[i][j]);
44             printf("%d\n",maze[i][9]);
45         }
46         over=true;
47         return ;
48     }
49     for(int i=1;i<=9;i++)
50     {
51         if(judge(cnt,i)&&!over)
52         {
53             maze[point[cnt].x][point[cnt].y]=i;
54             dfs(cnt+1);
55             maze[point[cnt].x][point[cnt].y]=0;
56         }
57     }
58 }
59 int main()
60 {
61     char s[3];
62     int p=0,i=1,j=1;
63     tot=1;
64     while(scanf("%s",&s)!=EOF)
65     {
66         if(s[0]!=‘?‘)
67         {
68             maze[i][j]=s[0]-‘0‘;
69         }
70         else
71         {
72             maze[i][j]=0;
73             point[tot].x=i;
74             point[tot++].y=j;
75         }
76         j++;
77         if(j>9)
78         {
79             i++;
80             j=1;
81         }
82         if(i==10)
83         {
84             if(p)
85                 printf("\n");
86             p++;
87             over=false;
88             dfs(1);
89             i=j=1;
90             tot=1;
91         }
92     }
93     return 0;
94 }