[Ybtoj High-efficiency Advanced 1.5] [Wide Search] Peaks and valleys

[Ybtoj High-efficiency Advanced 1.5] [Wide Search] Peaks and valleys

topic

---

Problem-solving ideas

Search widely for connected blocks to
determine whether all the circles around this connected block are less than or greater than ta. If
all is less than, it is a mountain. If
all is greater than, it is a valley.
Finally output the number of peaks and valleys

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Code

#include<iostream>
#include<cstring> 
#include<cstdio>
using namespace std;
struct lzf{
    
    
	int x,y;
}q[1000050];
int n,tz,ansmi,ansma;
int a[1005][1005],p[1005][1005],vis[1005][1005];
int fx[9]={
    
    0,1,1,0,-1,-1,-1,0,1},fy[9]={
    
    0,0,1,1,1,0,-1,-1,-1};
void bfs(int x,int y)
{
    
    
	 int h=0,t=1,mi=1,ma=1;
	 q[t].x=x,q[t].y=y;
	 vis[x][y]=1;
	 p[x][y]=1;
	 do{
    
    
	 	h++;
	 	for (int i=1;i<=8;i++)
	 	{
    
    
		    int xx=q[h].x+fx[i],yy=q[h].y+fy[i];
	 	    if (xx>0&&xx<=n&&yy>0&&yy<=n)  //判断是否能走
	 	       if (a[xx][yy]!=a[x][y])  //不是连通块内部，是周围的
	 	       {
    
    
				  if (a[x][y]>a[xx][yy]) mi=0; 
				  if (a[x][y]<a[xx][yy]) ma=0;  //记录状态
			   }
			   else if (!p[xx][yy])  //是否走过
			   {
    
    
			   	  q[++t].x=xx;
			   	  q[t].y=yy;
			   	  p[xx][yy]=1;
			   } 
        }
	 }while (h<t); 
	 if (!mi&&ma) ansmi++; 
	 if (!ma&&mi) ansma++;  //统计个数
}
int main()
{
    
    
    scanf("%d",&n);
	for (int i=1;i<=n;i++)
	    for (int j=1;j<=n;j++)	
	        scanf("%d",&a[i][j]);
	for (int i=1;i<=n;i++)
	    for (int j=1;j<=n;j++)
	        if (!p[i][j])
	        {
    
    
			   p[i][j]=1;
	           bfs(i,j); 
	           tz++;
	        }
	if (tz==1)  
	   printf("1 1\n");  //全部一样
	   else printf("%d %d\n",ansmi,ansma);
	return 0;
}