原题链接
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
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 OUTPUT DETAILS: There are three ponds: one in the upper left, one in the lower left,and one along the right side.
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AC代码：
#include <iostream>using namespace std;int n,m;char f[100][101]; void dfs(int x,int y){ int i,j; f[x][y]='.'; for(i=-1;i<=1;i++){ for(j=-1;j<=1;j++){ int dx=x+i; int dy=y+j; if(dx>=0 && dx<n && dy>=0 && dy<m && f[dx][dy]=='W') dfs(dx,dy); } } return;}int main(){ int i,j; cin>>n>>m; for(i=0;i<n;i++){ cin>>f[i]; } int res=0; for(i=0;i<n;i++){ for(j=0;j<m;j++){ if(f[i][j]=='W'){ dfs(i,j); res++; } } } cout<<res<<endl; return 0;}新闻热点
疑难解答
