counting sheep hdu 2952

Posted 2020-12-19 0211ji

dfs四个方向搜索

 1 #include<iostream>
 2 #include<algorithm>
 3 #include<queue>
 4 #include<stack>
 5 #include <bitset>
 6 #include<set>
 7 #include<map>
 8 #include<unordered_map>
 9 #include<vector>
10 #include<cmath>
11 #include<string>
12 using namespace std;
13 typedef long long ll;
14 typedef pair<int, int> p;
15 typedef unsigned long long ull;
16 
17 int t, h, w;
18 char mat[105][105];
19 int direc[4][2] = { {0,1},{1,0},{-1,0},{0,-1} };
20 int visited[105][105];
21 int sum;
22 
23 void dfs(int p,int q) {
24     for (int k = 0; k < 4; k++) {            
25         int nl = p + direc[k][0];
26         int nr = q + direc[k][1];
27         if (1 <= nl && nl <= h && 1 <= nr && nr <= w && visited[nl][nr] == 0 && mat[nl][nr] == ‘#‘) {
28             visited[nl][nr] = 1;
29             dfs(nl, nr);
30         }
31             
32         
33     }
34 }
35 int main() {
36     cin >> t;
37     while (t--) {
38         cin >> h >> w;
39         for (int i = 1; i <= h; i++) {
40             for (int j = 1; j <= w; j++) {
41                 cin >> mat[i][j];
42             }
43         }
44         memset(visited, 0, sizeof(visited));
45         sum = 0;
46         for (int i = 1; i <= h; i++) {
47             for (int j = 1; j <= w; j++) {
48                 if (mat[i][j] == ‘#‘ && visited[i][j] == 0) {
49                     visited[i][j] = 1;
50                     dfs(i, j);
51                     sum++;
52                 }
53             }
54         }
55         cout << sum << endl;
56     
57     }
58     return 0;
59 }