#include <iostream>
using namespace std;
struct Node
{
	double startx,starty;
	double endx,endy;
}s[100002];
bool signal[100002];
int ans[1002];
int Judge(Node a,Node b)
{
	double t1=(a.startx-b.endx)*(b.starty-b.endy)-(a.starty-b.endy)*(b.startx-b.endx);//叉积
	double t2=(b.starty-b.endy)*(a.endx-b.endx)-(b.startx-b.endx)*(a.endy-b.endy);
	double t3=(b.endx-a.startx)*(a.endy-a.starty)-(b.endy-a.starty)*(a.endx-a.startx);
	double t4=(a.endy-a.starty)*(b.startx-a.startx)-(a.endx-a.startx)*(b.starty-a.starty);
	if(t1*t2<0&&t3*t4<0)
		return 1;
	else
		return 0;
}

int main()
{
	int n;
	int i,j,t,count;
	while(scanf("%d",&n)!=EOF)
	{
		if(n==0)break;
		else
		{
			count=0;
			for(i=0;i<n;++i)
			{
				scanf("%lf%lf%lf%lf",&s[i].startx,&s[i].starty,&s[i].endx,&s[i].endy);
				getchar();
				signal[i]=true;
			}
			for(i=n-1;i>=0;--i)
			{
				if(signal[i]==true)
				{
					for(j=0;j<i;++j)
					{
						if(signal[j]==true)
						{
							t=Judge(s[i],s[j]);//线段s[i]和s[j]是否相交
							if(t==1)signal[j]=false;
						}
					}
					ans[count++]=i+1;
					if(count>1002)break;
				}
			}
			printf("Top sticks: ");
			for(i=count-1;i>0;--i)
			{
				printf("%d, ",ans[i]);
			}
			printf("%d.\n",ans[0]);
		}
	}
	return 0;
}

• 哪位大牛解释一下！ (1419) xiaohuang_17 2009-08-09 22:43:36
• Re:为什么WA啊！！！ (1419) 344431432 2009-11-27 17:36:38