题解:
简单灌水
从最高的开始
代码:
#include<bits/stdc++.h> const int inf=0x7fffffff,N=705; typedef long long ll; using namespace std; int n,m,cnt,ans,xx[8]={0,0,1,1,1,-1,-1,-1},yy[8]={1,-1,1,0,-1,1,0,-1},mp[N][N],mark[N][N]; struct data{int x,y,t;}a[500005]; bool operator<(data a,data b){return a.t>b.t;} void dfs(int x,int y) { mark[x][y]=1; for (int i=0;i<8;i++) { int nowx=x+xx[i],nowy=y+yy[i]; if (nowx<1||nowy<1||nowx>n||nowy>m)continue; if (mp[nowx][nowy]<=mp[x][y]&&!mark[nowx][nowy])dfs(nowx,nowy); } } int main() { scanf("%d%d",&n,&m); for (int i=1;i<=n;i++) for (int j=1;j<=m;j++) { cnt++; scanf("%d",&mp[i][j]); a[cnt].x=i;a[cnt].y=j;a[cnt].t=mp[i][j]; } sort(a+1,a+cnt+1); for (int i=1;i<=cnt;i++) if (!mark[a[i].x][a[i].y]){dfs(a[i].x,a[i].y);ans++;} printf("%d",ans); return 0; }