#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <iostream>
#include <algorithm>

using namespace std;
const int MAX=110;
const double eps = 1e-6;

struct point
{
    double x,y;
};

struct beline
{
    point a,b;
};

point p[MAX];
int n=0;
bool dy(double x,double y)
{
  return x>y+eps;
}
bool xy(double x,double y)
{
    return x<y-eps;
}
bool dyd(double x,double y)
{
    return x > y - eps;
}
bool xyd(double x,double y)
{
    return x<y+eps;
}
bool dd(double x,double y)
{
    return fabs(x-y) < eps;
}
double crossProduct(point a,point b,point c)
{
    return (c.x - a.x)*(b.y-a.y)-(b.x-a.x)*(c.y-a.y);
}
bool onSegment(point a,point b,point c)
{
    double maxx=max(a.x,b.x);
    double maxy=max(a.y,b.y);
    double minx=min(a.x,b.x);
    double miny=min(a.y,b.y);
    if(dd(crossProduct(a,b,c),0.0)&&dyd(c.x,minx)&&xyd(c.x,maxx)&&dyd(c.y,miny)&&xyd(c.y,maxy))
        return true;
    return false;
}

bool segIntersect(point p1,point p2,point p3,point p4)
{
    double d1 = crossProduct(p3,p4,p1);
    double d2 = crossProduct(p3,p4,p2);
    double d3 = crossProduct(p1,p2,p3);
    double d4 = crossProduct(p1,p2,p4);
    if(xy(d1 * d2,0.0)&&xy(d3*d4,0.0))
        return true;
    if(dd(d1,0.0)&&onSegment(p3,p4,p1))
        return true;
    if(dd(d2,0.0)&&onSegment(p3,p4,p2))
        return true;
    if(dd(d3,0.0)&&onSegment(p1,p2,p3))
        return true;
    if(dd(d4,0.0)&&onSegment(p1,p2,p4))
        return true;
    return false;
}


int main()
{
    int cas,i,j;
    while(scanf("%d",&cas)!=EOF&&cas!=0)
    {
         beline L[MAX];
         n=0;
         for(i=0;i<cas;i++)
         {
             scanf("%lf%lf%lf%lf",&L[i].a.x,&L[i].a.y,&L[i].b.x,&L[i].b.y);
         }
         for(i=0;i<cas;i++)
         {
             for(j=i+1;j<cas;j++)
                 if(segIntersect(L[i].a,L[i].b,L[j].a,L[j].b))
                 {
                     n++;
                 }
         }
         printf("%d\n",n);
    }
    return 0;
}