hihocoder offer收割编程练习赛8 B

思路：

模拟，dfs。

注意题目中的trick，输出一块的时候不要把其他块也输出了。

实现：

 1 #include <cstring>
 2 #include <iostream>
 3 #include <cstdio>
 4 #include <algorithm>
 5 using namespace std;
 6
 7 char a[505][505];
 8 int n, m, minx, miny, maxx, maxy;
 9 bool vis[505][505], ok[505][505];
10 int dx[4] = { 0, 1, 0, -1 };
11 int dy[4] = { 1, 0, -1, 0 };
12
13 void dfs(int x, int y)
14 {
15     ok[x][y] = vis[x][y] = true;
16     minx = min(x, minx);
17     miny = min(y, miny);
18     maxx = max(x, maxx);
19     maxy = max(y, maxy);
20     for (int i = 0; i < 4; i++)
21     {
22         int nx = x + dx[i];
23         int ny = y + dy[i];
24         if (nx >= 0 && nx < n && ny >= 0 && ny < m && !vis[nx][ny] && a[nx][ny] == ‘1‘)
25         {
26             dfs(nx, ny);
27         }
28     }
29 }
30 int main()
31 {
32     cin >> n >> m;
33     for (int i = 0; i < n; i++)
34     {
35         for (int j = 0; j < m; j++)
36         {
37             cin >> a[i][j];
38         }
39     }
40     for (int j = 0; j < m; j++)
41     {
42         for (int i = 0; i < n; i++)
43         {
44             if (!vis[i][j] && a[i][j] == ‘1‘)
45             {
46                 minx = maxx = i, miny = maxy = j;
47                 memset(ok, 0, sizeof(ok));
48                 dfs(i, j);
49                 cout << maxx - minx + 1 << " " << maxy - miny + 1 << endl;
50                 for (int j = minx; j <= maxx; j++)
51                 {
52                     for (int k = miny; k <= maxy; k++)
53                     {
54                         cout << ok[j][k];
55                     }
56                     cout << endl;
57                 }
58             }
59         }
60     }
61     return 0;
62 }