Bzoj 3385: [usaco Nov] Lake counting data Pond

Question 3385: [usaco 2004 Nov] Lake counting pond time limit: 1 sec memory limit: 128 MB
Description Farmer John's farm can be represented as a rectangle consisting of n × m (1 ≤ n, m ≤ 100) Square. due to recent rainfall, ponds are formed in different places on John's farm. each square or with water ('W') or without water ('. '). farmer John planned to figure out how many ponds he had formed on his farm. A pond is a series of squares connected with water. The eight squares around each square are considered to be connected to this square. the figure of John's farm is given, requesting the number of ponds on the farm to be output. row 1st of input: two integers n and m separated by spaces. rows 2nd to n + 1: m characters in each line represent the state of a row of squares at John farm. each character is either 'W' or '. ', there is no space between characters. number of ponds on the output John farm.

 

Sample input10 12
W ...... ww.
. Www... www
... Ww... ww.
......... Ww.
..
... W ..
. W. w... ww.
W. W. W... w.
. W. w... w.
... W... W. Sample output3hint

 

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

Question

I used floodfill to do this. Oh, time rank goes down first =

Code

 1 /*Author:WNJXYK*/ 2 #include<cstdio> 3 #include<iostream> 4 using namespace std; 5 int n,m; 6 const int Maxn=100; 7 bool map[Maxn+10][Maxn+10]; 8 bool visited[Maxn+10][Maxn+10];  9 inline char read(){10     char ch=getchar();11     while(ch!=‘.‘ && ch!=‘W‘) ch=getchar();12     return ch;13 } 14 int cnt=0;15 int dx[]={0,-1,-1,0,1,1,1,0,-1};16 int dy[]={0,0,1,1,1,0,-1,-1,-1};17 void floodfill(int x,int y){18     visited[x][y]=true;19     for (int k=1;k<=8;k++){20         int nx=x+dx[k],ny=y+dy[k];21         if (1<=nx && nx<=n && 1<=ny && ny<=m)22             if (map[nx][ny]==true)23                 if (visited[nx][ny]==false)24                     floodfill(nx,ny);25     }26 }27 28 int main(){29     scanf("%d%d",&n,&m);30     for (int i=1;i<=n;i++){31         for (int j=1;j<=m;j++){32             char ch=read();33             if (ch==‘.‘) map[i][j]=false;34             if (ch==‘W‘) map[i][j]=true;35             visited[i][j]=false;36         }37     }38     for (int i=1;i<=n;i++){39         for (int j=1;j<=m;j++){40             if (visited[i][j]==false&&map[i][j]==true){41                 floodfill(i,j);42                 cnt++;43             } 44         } 45     }46     printf("%d\n",cnt);47     return 0;48 }

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Bzoj 3385: [usaco Nov] Lake counting data Pond