hdu 1312 Red and Black(dfs入门)

 1 #include <iostream>
 2 #include <cstdio>
 3 char map[21][21];
 4 int H, W, starti, startj, num;                        //H行 W列
 5 int dir[4][2] = {{-1,0}, {0,1}, {1,0}, {0,-1}};
 6 void dfs(int x, int y)
 7 {
 8     ++num;
 9     for (int i = 0; i < 4; ++i)
10     {
11         int fx = x + dir[i][0];
12         int fy = y + dir[i][1];
13         if (fx>=0 && fx<H && fy>=0 && fy<W && map[fx][fy] == '.')
14         {
15             map[fx][fy] = '#';
16             dfs(fx, fy);
17         }
18     }
19 }
20 int main()
21 {
22 #ifndef ONLINE_JUDGE
23     freopen("in.txt", "r", stdin);
24 #endif
25     while (scanf("%d %d", &W, &H) != EOF && W)
26     {
27         for (int i = 0; i < H; ++i)
28             for (int j = 0; j < W; ++j)
29             {
30                 std::cin >> map[i][j];
31                 if (map[i][j] == '@')
32                 {
33                     starti = i;
34                     startj = j;
35                 }
36             }
37         map[starti][startj] = '#';
38         num = 0;
39         dfs(starti, startj);
40         printf("%d\n", num);
41     }
42     return 0;
43 }
posted on 2013-04-06 12:46 PegasusWang 阅读(328) 评论(0) 编辑收藏举报