dfs hdu1241 Oil Deposits

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
0
1
2
2

题意概况：@代表油田，上下左右斜上斜下相连的都算作一个油田，问有多少个油田？

解题思路：把图上的每个@都读一遍，如果还未走过就进入深搜函数，如果走过跳过该@,有多少@进入函数即有多少油田。

代码：

#include<stdio.h>#include<string.h>int m,n,t,l,book[150][150];char s[150][150];void dfs(int x,int y){int tx=0,ty=0,k;int next[8][2]={{0,1},{1,0},{0,-1},{-1,0},{1,1},{1,-1},{-1,1},{-1,-1}};for(k=0;k<=7;k++){tx=x+next[k][0];ty=y+next[k][1];if(tx>m||tx<1||ty>n||ty<1)continue;//printf("%d %d++\n\n",tx,ty);if(s[tx][ty]=='@'&&book[tx][ty]==0){book[tx][ty]=1;dfs(tx,ty);//book[tx][ty]=0;}} return ;}int main(){int i,j,t1,t2,t3;while(scanf("%d%d\n",&m,&n)!=EOF){if(m==0&&n==0)          break;memset(book,0,sizeof(book));t1=0;//getchar();for(i=1;i<=m;i++){scanf("\n");for(j=1;j<=n;j++){scanf("%c",&s[i][j]);}}for(i=1;i<=m;i++){for(j=1;j<=n;j++){if(s[i][j]=='@'){if(book[i][j]==1)continue;else{//printf("++%d %d\n",i,j);book[i][j]=1;dfs(i,j);t1++;}}}}printf("%d\n",t1);getchar();}return 0;}