POJ 2386 Lake Counting

此题和HDU 1241 Oil Deposites题意是一样的，区别仅仅是表示的字符不一样（一个数油田一个数水洼→_→）。（HDU 1241题目链接已附在结尾处）题意很简单，输入两个整数N和M，表示一个N行M列的一块地，由输入的'W'和'.'组成，W代表该位置是水，'.'代表该位置是干地。相连的W组成一块水洼(相连指8个方向相连，即上、下、左、右、左上、左下、右上、右下)，求出一共有多少个水洼。 经典dfs，直接看代码吧~

Lake Counting

Time Limit: 1000MS Memory Limit: 65536KTotal Submissions: 23890 Accepted: 12067

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 12W........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

OUTPUT DETAILS: 

There are three ponds: one in the upper left, one in the lower left,and one along the right side.

题目传送门：POJ2386 Lake Counting

AC代码：

#include <iostream>#include <cstdio>#include <cstring>using namespace std;char maze[105][105];int N,M;void dfs(int x,int y){    if(x<0 || x>=N || y<0 || y>=M || maze[x][y]!='W')        return;    else    {        dfs(x+1,y);        dfs(x-1,y);        dfs(x,y+1);        dfs(x,y-1);        dfs(x-1,y-1);        dfs(x+1,y-1);        dfs(x-1,y+1);        dfs(x+1,y+1);    }}int main(){    int sum=0;    scanf("%d%d",&N,&M);    for(int i=0;i<N;i++)        for(int j=0;j<M;j++)            cin>>maze[i][j];    for(int i=0;i<N;i++)    {        for(int j=0;j<M;j++)        {            if(maze[i][j]=='W')                {                    dfs(i,j);                    sum++;                }        }    }    return 0;}

附：HDU1241 Oil Deposits题解&代码  HDU1241题目传送门：HDU1241 Oil Deposits