| 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.
and 
.
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.
1 1 * 3 5 *@*@* **@** *@*@* 1 8 @@****@* 5 5 ****@ *@@*@ *@**@ @@@*@ @@**@ 0 0
0 1 2 2
题意 计算@连通块的数量 典型的dfs应用
#include<cstdio>
#include<cstring>
using namespace std;
#define r i+x[k]
#define c j+y[k]
const int N = 105;
char mat[N][N];
int n, x[8] = { -1, -1, -1, 0, 0, 1, 1, 1};
int m, y[8] = { -1, 0, 1, -1, 1, -1, 0, 1};
int dfs (int i, int j)
{
if (mat[i][j] == '*') return 0;
mat[i][j] = '*';
for (int k = 0; k < 8; ++k)
if (r > 0 && r <= n && c > 0 && c <= m && mat[r][c] == '@')
dfs (r, c);
return 1;
}
int main()
{
while (scanf ("%d%d", &n, &m), n)
{
int ans = 0;
for (int i = 1; i <= n; ++i)
scanf ("%s", mat[i] + 1);
for (int i = 1; i <= n; ++i)
for (int j = 1; j <= m; ++j)
ans += dfs (i, j);
printf ("%d\n", ans);
}
return 0;
}
UVa 572 Oil Deposits(DFS),布布扣,bubuko.com
原文地址：http://blog.csdn.net/iooden/article/details/38374187
