水题 ~~~啥都不说了
水方法解决
#include<string.h>
#include <stdio.h>

int x1, y1, x2, y2;

double seg[100000][2];
int cnt;
int res;

int segb[100000];
double total[100000][2];

int xl,yl;

void shadow()
{
    double x=xl,y=yl;
    double ax=x1,ay=y1,bx=x2,by=y2;

    double d1,d2;
    d1=x-y*(x-ax)/(y-ay);
    d2=x-y*(x-bx)/(y-by);
    if(d1>d2)
    {
        double hold=d1;
        d1=d2;
        d2=hold;
    }
    seg[cnt][0]=d1;
    seg[cnt][1]=d2;
    segb[cnt]=1;
    cnt++;
}


void cacul()
{
    int i=0;
    while(i<cnt)
    {    
        for(int l=0;l<cnt;l++)
        {
            if(segb[l]==1)
            {            
                total[res][0]=seg[l][0];
                total[res][1]=seg[l][1];
                segb[l]=0;
                res++;
                i++;
                break;
            }
        }
        for(int j=0;j<res;j++)
        {
            int k=0;
            for(k=0;k<cnt;k++)
            {
                if(segb[k]==1)
                {
                    if(total[j][0]-seg[k][0]>=0 && seg[k][1]-total[j][0]>=0)
                    {
                        total[j][0]=seg[k][0];
                        if(seg[k][1]-total[j][1]>=0)
                            total[j][1]=seg[k][1];
                        i++;
                        segb[k]=0;
                        k=0;
                    }
                    else
                    if(total[j][1]-seg[k][0]>=0 && seg[k][1]-total[j][1]>=0)
                    {
                        total[j][1]=seg[k][1];
                        if(total[j][0]-seg[k][0]>=0)
                            total[j][0]=seg[k][0];        
                        i++;
                        segb[k]=0;
                        k=0;
                    }
                    else
                    if(seg[k][0]-total[j][0]>=0 && total[j][1]-seg[k][1]>=0)
                    {
                        i++;
                        segb[k]=0;
                        k=0;
                    }
                }
            }
        }

    }
}

int main()
{
    int n;
    scanf("%d",&n);
    for(int i=0;i<n;i++)
    {
        memset(seg,0,sizeof(seg));
        memset(total,0,sizeof(total));
        memset(segb,0,sizeof(segb));
        cnt=0;
        res=0;
        int m;
        scanf("%d",&m);
        scanf("%d%d",&xl,&yl);
        for(int j=0;j<m;j++)
        {
            scanf("%d%d%d%d",&x1,&y1,&x2,&y2);
            shadow();
        }
        cacul();
        printf("%d\n",res+1);
    }

    return 0;    
}