*寒假水107——搜索【深搜】

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本文介绍了一种用于探测地下油藏分布的算法实现。通过构建网格模型并运用搜索算法确定不同油藏的数量，该方法能够有效处理大规模土地区域的数据分析工作。

The GeoSurvComp geologic survey company is responsible for detecting underground oil deposits. GeoSurvComp works with one large rectangular region of land at a time, and creates a grid that divides the land into numerous square plots. It then analyzes each plot separately, using sensing equipment to determine whether or not the plot contains oil. A plot containing oil is called a pocket. If two pockets are adjacent, then they are part of the same oil deposit. Oil deposits can be quite large and may contain numerous pockets. Your job is to determine how many different oil deposits are contained in a grid.

Input

The input contains one or more grids. Each grid begins with a line containing m and n, the number of rows and columns in the grid, separated by a single space. If m = 0 it signals the end of the input; otherwise 1 <= m <= 100 and 1 <= n <= 100. Following this are m lines of n characters each (not counting the end-of-line characters). Each character corresponds to one plot, and is either `*', representing the absence of oil, or `@', representing an oil pocket.

Output

are adjacent horizontally, vertically, or diagonally. An oil deposit will not contain more than 100 pockets.

Sample Input

1 1
*
3 5
*@*@*
**@**
*@*@*
1 8
@@****@*
5 5 
****@
*@@*@
*@**@
@@@*@
@@**@
0 0

Sample Output

#include<iostream>
#include<stdio.h>

using namespace std;

char map[101][101];
int a,b;
int dir[8][2]={1,1, 1,-1, -1,1, -1,-1, 0,1, 0,-1, 1,0, -1,0};

void bfs(int x,int y)
{
 int i,n,m;
 for(i=0;i<8;i++)
 {
  n=x+dir[i][0];
  m=y+dir[i][1];
     if(n<0||m<0||n>a-1||m>b-1||map[n][m]=='*')
      continue;
     map[n][m]='*';
  bfs(n,m);
 }
}

int main()
{
 int i,j,count;
 while(cin>>a>>b,a||b)
 {
  count=0;
  for(i=0;i<a;i++)
   scanf("%s",map[i]);
  for(i=0;i<a;i++)
  {
   for(j=0;j<b;j++)
   {
    if(map[i][j]=='@')
    {
     map[i][j]='*';
     bfs(i,j);
     count++;
    }
   }
  }
  cout<<count<<endl;
 }
 return 0;
}

题解：深搜，尽在不言中。