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#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#define INF 0x3f3f3f3f

using namespace std;

const int maxn = 105;

struct Point
{
    double x,y;
} line[maxn][2];

bool judge(Point &a,Point &b,Point &c,Point &d)
{

    if(!(min(a.x,b.x)<=max(c.x,d.x) && min(c.y,d.y)<=max(a.y,b.y)&&min(c.x,d.x)<=max(a.x,b.x) && min(a.y,b.y)<=max(c.y,d.y)))
        return false;
    double u,v,w,z;
    u=(c.x-a.x)*(b.y-a.y)-(b.x-a.x)*(c.y-a.y);
    v=(d.x-a.x)*(b.y-a.y)-(b.x-a.x)*(d.y-a.y);
    w=(a.x-c.x)*(d.y-c.y)-(d.x-c.x)*(a.y-c.y);
    z=(b.x-c.x)*(d.y-c.y)-(d.x-c.x)*(b.y-c.y);
    return (u*v<=0.00000001 && w*z<=0.00000001);
}

int main()
{
    int n;
    scanf("%d",&n);
    bool flag = true;
    for(int i = 0; i < n; i ++)
    {
        scanf("%lf%lf%lf%lf",&line[i][0].x,&line[i][0].y,&line[i][1].x,&line[i][1].y);
    }

    int cnt=0;
    for(int i = 0; i < n; i ++)
        for(int j = i+1; j < n; j ++)
        {
            if(judge(line[i][0],line[i][1],line[j][0],line[j][1]))
            {
                cnt++;
            }
        }
    printf("%d\n",cnt);
    return 0;
}

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