求两直线的关系并求交点

/************************************************************
 求两直线关系
 poj 1269
 求两直线是相交 平行 还是重合 相交则求出交点 
 * *********************************************************/

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 

using namespace std;
const double eps = 1e-8;
int sgn(double x)
{
    if(fabs(x) < eps)return 0;
    if(x < 0)return -1;
    else return 1;
}
struct Point
{
    double x,y;
    Point(){}
    Point(double _x,double _y)
    {
        x = _x;y = _y;
    }
    Point operator -(const Point &b)const
    {
        return Point(x - b.x,y - b.y);
    }
    double operator ^(const Point &b)const
    {
        return x*b.y - y*b.x;
    }
    double operator *(const Point &b)const
    {
        return x*b.x + y*b.y;
    }
};
struct Line
{
    Point s,e;
    Line(){}
    Line(Point _s,Point _e)
    {
        s = _s;e = _e;
    }
    pairint> operator &(const Line &b)const
    {
        Point res = s;
        if(sgn((s-e)^(b.s-b.e)) == 0)
        {
            if(sgn((b.s-s)^(b.e-s)) == 0)
                return make_pair(res,0);//两直线重合
            else return make_pair(res,1);//两直线平行
        }
        double t = ((s-b.s)^(b.s-b.e))/((s-e)^(b.s-b.e));
        res.x += (e.x - s.x)*t;
        res.y += (e.y - s.y)*t;
        return make_pair(res,2);//有交点
    }
};
int main()
{
    //freopen("in.txt","r",stdin);
    //freopen("out.txt","w",stdout);
    int T;
    scanf("%d",&T);
    double x1,y1,x2,y2,x3,y3,x4,y4;
    printf("INTERSECTING LINES OUTPUT\n");
    while(T--)
    {
        scanf("%lf%lf%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);
        Line line1 = Line(Point(x1,y1),Point(x2,y2));
        Line line2 = Line(Point(x3,y3),Point(x4,y4));
        pairint> ans = line1 & line2;
        if( ans.second == 2)printf("POINT %.2lf %.2lf\n",ans.first.x,ans.first.y);
        else if(ans.second == 0)printf("LINE\n");
        else printf("NONE\n");
    }
    printf("END OF OUTPUT\n");

    return 0;
}