Bzoj1102: [poi2007] Mountain and valley grz

1102: [poi2007] Mountain and valley grztime limit: 10 sec memory limit: 162 MB
Submit: 436 solved: 227
[Submit] [Status] Description

FGD is especially fond of mountain climbing. He is studying mountain peaks and valleys. In order for him to have an arrangement on his journey, he wanted to know the number of mountains and valleys.
Given a map, for the area that FGD wants to travel, the map is divided into N * n grids, and the height of each grid (I, j) is W (I, j) given.
If two grids have common vertices, they are adjacent grids. (So the grids adjacent to (I, j) are (I-1, J-1), (I-1, J), (I-1, J + 1 ), (I, j-1), (I, j + 1), (I + 1, J-1), (I + 1, J), (I + 1, J + 1 )).
We define a grid set S as a mountain (Valley) When and only when:
All the grids of 1. s have the same height.
2. All grids of S are connected
3. If s belongs to S, and s Adjacent to S does not belong to S. There are ws> ws '(mountain) or ws <ws' (Valley ).
Your task is to find the number of peaks and valleys for a given map. If all grids have the same height, the whole map is a mountain and a valley.

Input

The first line contains a positive integer N, indicating the map size (1 <= n <= 1000 ). The next N * n matrix represents the height of each grid on the map. (0 <= W <= 1000000000)

Output

It should contain two numbers, indicating the number of mountain and valley, respectively.

Sample input Example 1
5
8 8 8 7 7
7 7 8 8 7
7 7 7 7 7
7 8 8 7 8
7 8 8 8 8
Input Example 2
5
5 7 8 3 1
5 5 7 6 6
6 6 6 2 8
5 7 2 5 8
7 1 0 1 7 sample output sample 1
2 1
Output Example 2
3 3
Hint

Source

Question:

I don't need to write any code...

Post a personal

 1 #include <iostream> 2 #include <cstdio> 3 #include <cstring> 4 #include <cstdlib> 5 using namespace std; 6    7 const int px[8]={-1,-1,0,1,1,1,0,-1}; 8 const int py[8]={0,1,1,1,0,-1,-1,-1}; 9 int map[1001][1001],x[1000001],y[1000001],n,valleys,ridges;10 bool vis[1001][1001];11   12 bool check(int pos,char sym){13     for(int k=1;k<=pos;k++)14         for(int i=0;i<8;i++){15             int xx=x[k]+px[i],yy=y[k]+py[i];16             if(!(xx>0&&xx<=n&&yy>0&&yy<=n)) continue;17             if((sym==‘v‘&&map[xx][yy]<map[x[k]][y[k]])||(sym==‘r‘&&map[xx][yy]>map[x[k]][y[k]])) return false;18         }19     return true;20 }         21   22 void bfs(int posx,int posy){23     int head=1,tail=0,xx,yy;24     x[++tail]=posx,y[tail]=posy;25     while(head<=tail){26         for(int i=0;i<8;i++){27             xx=x[head]+px[i],yy=y[head]+py[i];28             if(!(xx>0&&xx<=n&&yy>0&&yy<=n&&map[xx][yy]==map[posx][posy]&&!vis[xx][yy])) continue;29             vis[xx][yy]=true;30             x[++tail]=xx,y[tail]=yy;31         }32         head++;33     }34     if(check(tail,‘v‘)) valleys++;35     if(check(tail,‘r‘)) ridges++;36 }37   38 int main(){39     scanf("%d",&n);40     for(int i=1;i<=n;i++)41         for(int j=1;j<=n;j++) scanf("%d",&map[i][j]);42     memset(vis,false,sizeof(vis));43     for(int i=1;i<=n;i++)44         for(int j=1;j<=n;j++)45             if(!vis[i][j]) bfs(i,j);46     printf("%d %d\n",ridges,valleys);47     return 0;48 }

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Bzoj1102: [poi2007] Mountain and valley grz