Lake Counting

Description

Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1 <= M <= 100) squares. Each square contains either water ('W') or dry land ('.'). Farmer John would like to figure out how many ponds have formed in his field. A pond is a connected set of squares with water in them, where a square is considered adjacent to all eight of its neighbors.

Given a diagram of Farmer John's field, determine how many ponds he has.

Input

* Line 1: Two space-separated integers: N and M

* Lines 2..N+1: M characters per line representing one row of Farmer John's field. Each character is either 'W' or '.'. The characters do not have spaces between them.

Output

* Line 1: The number of ponds in Farmer John's field.

Sample Input

10 12
W........WW.
.WWW.....WWW
....WW...WW.
.........WW.
.........W..
..W......W..
.W.W.....WW.
W.W.W.....W.
.W.W......W.
..W.......W.

Sample Output

 1 #include<stdio.h>
 2 #include<string.h>
 3 #include<algorithm>
 4 #include<stack>
 5 #include<queue>
 6 #include<deque>
 7 #include<vector>
 8 using namespace std;
 9 char str[500][500],m,n;
10 void dfs(int x,int y)
11 {
12     int i,j;
13     str[x][y]='.';
14     for(i=-1;i<=1;i++)
15         for(j=-1;j<=1;j++)
16     {
17         if(x+i>=0&&x+i<m&&y+j>=0&&y+j<n&&str[x+i][y+j]=='W')
18             dfs(x+i,y+j);
19     }
20 }
21 int main()
22 {
23     int i,j;
24     scanf("%d%d",&m,&n);
25 
26         getchar();
27         int ans=0;
28         for(i=0; i<m; i++)
29             scanf("%s",&str[i]);
30         for(i=0; i<m; i++)
31             for(j=0; j<n; j++)
32             {
33                 if(str[i][j]=='W')
34                 {
35                     dfs(i,j);
36                     ans++;
37                 }
38             }
39             printf("%d
",ans);
40 
41 }