Lake Counting

POJ 2386 Lake Counting

//POJ NO.2386 LAKE COUNTING
#include <iostream>
#include <cstdio>
using namespace std;
	int N,M;
	const int Max = 10000;
	char field[Max][Max+1]; //園子
	void dfs(int x,int y){
		field[x][y]='.';
		for (int dx=-1;dx<=1;dx++){
			for(int dy=-1;dy<=1;dy++){
				int nx=x+dx;int ny=y+dy;
				if(0<=nx && nx<N && 0<=ny && ny<M && field[nx][ny]=='W'){
					dfs(nx,ny);
				}
			}
		}
		return ;
	}
	void slove(){
		int res=0;
		cin >> N;
		cin >> M;
		for (int i=0;i<N;i++){
			for (int j=1;j<M;j++){
				cin >> field[i][j];
			}
		}
		for(int i=0;i<N;i++){
			for (int j=0;j<M;j++){
				if(field[i][j]=='W'){
				dfs(i,j);
				res++;
				}
			}
		}
		cout << res;
	}
	int main (){
		slove();
	}