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

3

#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<stack>
#include<queue>
#include<deque>
#include<vector>
using namespace std;
char str[500][500],m,n;
void dfs(int x,int y)
{
    int i,j;
    str[x][y]='.';
    for(i=-1;i<=1;i++)
        for(j=-1;j<=1;j++)
    {
        if(x+i>=0&&x+i<m&&y+j>=0&&y+j<n&&str[x+i][y+j]=='W')
            dfs(x+i,y+j);
    }
}
int main()
{
    int i,j;
    scanf("%d%d",&m,&n);

        getchar();
        int ans=0;
        for(i=0; i<m; i++)
            scanf("%s",&str[i]);
        for(i=0; i<m; i++)
            for(j=0; j<n; j++)
            {
                if(str[i][j]=='W')
                {
                    dfs(i,j);
                    ans++;
                }
            }
            printf("%d\n",ans);

}