2019.9.14校内考试

T1：

　　　发现正方形棋盘，其边长为2^k（1<k<10），而且2^k（1<k<10）-1能被3整除，就想到了分治（主要还是qbzt的老师讲过）。每次将大棋盘从中间分成4个正方形的小棋盘，根据坏点在第几个棋盘分类处理，最后在棋盘大小分为2的时候就可以结束递归了。

AC代码：

 1 #include<iostream>
 2 #include<cstdio>
 3 
 4 using namespace std;
 5 
 6 int a,map[514][514],len[10]={1,2,4,8,16,32,64,128,256,512},k,ex,ey;
 7 
 8 void erfen(int zx,int zy,int yx,int yy,int hx,int hy)
 9 {
10     int zhongx=(zx+yx)>>1,zhongy=(zy+yy)>>1;
11     if(zhongx==zx&&zhongy==zy)//最后要终止递归时在分类把小棋盘剩下的未确认数的点填一下 
12     {
13         if(zx==hx&&zy==hy)
14         {
15             map[zx+1][zy]=map[zx+1][zy+1]=map[zx][zy+1]=4;
16         }
17         if(zx==hx&&zy+1==hy)
18         {
19             map[zx][zy]=map[zx+1][zy]=map[zx+1][zy+1]=3;
20         }
21         if(zx+1==hx&&zy==hy)
22         {
23             map[zx][zy]=map[zx][zy+1]=map[zx+1][zy+1]=2;
24         }
25         if(zx+1==hx&&zy+1==hy)
26         {
27             map[zx][zy]=map[zx+1][zy]=map[zx][zy+1]=1;
28         }
29         return;
30     }
31     if(hx<=zhongx&&hy<=zhongy)//已经确定数的点在左上
32     {
33         map[zhongx+1][zhongy+1]=map[zhongx+1][zhongy]=map[zhongx][zhongy+1]=4;
34         erfen(zx,zy,zhongx,zhongy,hx,hy);
35         erfen(zhongx+1,zy,yx,zhongy,zhongx+1,zhongy);
36         erfen(zx,zhongy+1,zhongx,yy,zhongx,zhongy+1);
37         erfen(zhongx+1,zhongy+1,yx,yy,zhongx+1,zhongy+1);
38     }
39     if(hx>zhongx&&hy<=zhongy)//已经确定数的点在左下 
40     {
41         map[zhongx+1][zhongy+1]=map[zhongx][zhongy]=map[zhongx][zhongy+1]=2;
42         erfen(zx,zy,zhongx,zhongy,zhongx,zhongy);
43         erfen(zhongx+1,zy,yx,zhongy,hx,hy);
44         erfen(zx,zhongy+1,zhongx,yy,zhongx,zhongy+1);
45         erfen(zhongx+1,zhongy+1,yx,yy,zhongx+1,zhongy+1);
46     }
47     if(hx<=zhongx&&hy>zhongy)//在右上 
48     {
49         map[zhongx+1][zhongy+1]=map[zhongx][zhongy]=map[zhongx+1][zhongy]=3;
50         erfen(zx,zy,zhongx,zhongy,zhongx,zhongy);
51         erfen(zhongx+1,zy,yx,zhongy,zhongx+1,zhongy);
52         erfen(zx,zhongy+1,zhongx,yy,hx,hy);
53         erfen(zhongx+1,zhongy+1,yx,yy,zhongx+1,zhongy+1);
54     }
55     if(hx>zhongx&&hy>zhongy)//在右下 
56     {
57         map[zhongx][zhongy+1]=map[zhongx][zhongy]=map[zhongx+1][zhongy]=1;
58         erfen(zx,zy,zhongx,zhongy,zhongx,zhongy);
59         erfen(zhongx+1,zy,yx,zhongy,zhongx+1,zhongy);
60         erfen(zx,zhongy+1,zhongx,yy,zhongx,zhongy+1);
61         erfen(zhongx+1,zhongy+1,yx,yy,hx,hy);
62     }
63 }
64 
65 void print()//输出矩阵 
66 {
67     for(int i=1;i<=a;i++)
68     {
69         for(int j=1;j<a;j++)
70             putchar(map[i][j]+'0'),putchar(' ');
71         putchar(map[i][a]+'0'),putchar('\n');
72     }
73 }
74 
75 int main()
76 {
77     freopen("chessboard.in","r",stdin);
78     freopen("chessboard.out","w",stdout);
79     cin>>k>>ey>>ex;
80     a=len[k];
81     map[ex][ey]=7;
82     erfen(1,1,a,a,ex,ey);
83     print();
84     return 0;
85 } 

View Code