池塘问题（深搜）

题目：

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

Hint

大体意思就是找W被.分成了多少块。

下面是一个正确的代码。

#include
#define MAXN 110
char ww[MAXN][MAXN];
int vis[MAXN][MAXN];
int f=0;
int n,m;

void search(int x,int y)
{


    if(x<0||x>=n||y<0||y>=m||vis[x][y]||ww[x][y]=='.') return;
    vis[x][y]=1;
    search(x+1,y);
    search(x+1,y+1);
	search(x+1,y-1);
	search(x-1,y);
	search(x-1,y+1);
	search(x-1,y-1);
	search(x,y+1);
	search(x,y-1);

}

main()
{
	char z;
	int i,j;

	int x,y;
	for(i=0;i

下面是一个错误的代码：

#include
#define MAXN 110
char ww[MAXN][MAXN];
int vis[MAXN][MAXN];
int f=0;

void search(int x,int y)
{
	vis[x][y]=1;
	if(!vis[x][y]&&ww[x][y]=='W')
	{
		search(x+1,y);
		search(x+1,y+1);
		search(x+1,y-1);
		search(x-1,y);
		search(x-1,y+1);
		search(x-1,y-1);
		search(x,y+1);
		search(x,y-1);
	}
}

main()
{
	int i,j;
	int n,m;
	int x,y;
	for(i=0;i

上面的代码中有两处错误，但是我不知道具体哦原因。

一处是gerchar的使用会使编译器报错。

另一处是深搜函数有问题，可能不执行递归。

没有进行调试，具体原因不清楚。