1 #include<stdio.h>
 2 #include<stdlib.h>
 3 int N, M;
 4 char field[3][3] =
 5 {
 6     { 'W','*','*'},
 7     { '*','W','*'},
 8     { '*','*','*'},
 9 };
10 void dfs(int x,int y) {
11     field[x][y] = '*';
12     
13     for (int dx = -1; dx <= 1; dx++){
14         for (int dy = -1
 
; dy <= 1; dy++) {
15             int nx = x + dx, ny = y + dy;
16             if (0 <= nx && nx < N && 0 <= ny && ny < M&&field[nx][ny] == 'W')
17                 dfs(nx, ny);
18         }
19     }
20     return;
21 }
22 
23 void solve() {
24     int res = 0
 
;
25     for (int i = 0; i < N; i++) {
26         for (int j = 0; j < M; j++) {
27             if (field[i][j] == 'W') {
28                 dfs(i, j);
29                 res++;
30             }
31         }
32     }
33     printf("%d", res);    
34 }
35 
36 int main() {
37     scanf("%d%d", &N,&M);
 
38     solve();
39    // system("pause");
40     return 0;
41 }

從任意w 開始 不停地把臨接部分用“*”代替

直到圖中不再存在W