UVa572——Oil Deposits——简单

最新推荐文章于 2021-05-26 22:19:09 发布

原创最新推荐文章于 2021-05-26 22:19:09 发布 · 261 阅读

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本文介绍了一种用于探测地下油藏的算法，通过将土地划分为网格并使用深度优先搜索(DFS)来确定不同油藏的数量。算法适用于图论和迷宫问题，是算法竞赛入门的经典案例。

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.

题目说明
算法竞赛入门经典上关于图和DFS的一道入门题。可通过这道题开始学习有关最短路、迷宫，贪心之类的算法。

#include <stdio.h>
char a[103][103];
int b[103][103]={0};
int n,m,cnt=0;
void dfs(int x,int y)
{
	int i,j;
				a[x][y]='.';
		for(i=-1;i<=1;i++)
		for(j=-1;j<=1;j++)
		{
			if((x+i<n&&y+j<m&&x+i>0&&y+i>0)&&a[x+i][y+j]=='@')
			{
				a[x+i][y+j]='.';
				dfs(x+i,y+j);
			}
		}
	}

int main()
{
	int i,j;
	while(~scanf("%d%d",&n,&m))
	{
		for(i=0;i<n;i++)
		{
			scanf("%s",&a[i]);
		}
		
		for(i=0;i<n;i++)
		{
			for(j=0;j<m;j++)
			{
				if(a[i][j]=='@')
				{
					dfs(i,j);
					cnt++;
				}
			}
		}
		printf("%d\n",cnt);
	}
}