hdu1071

#include<stdio.h>
#include<iostream>
using namespace std;
struct point 
{
double x,y;
}po[3];
double find_a(double x,double y,double x0,double y0)
{
return (y-y0)/((x-x0)*(x-x0));
}
double find_b(double x1,double y1,double x2,double y2)
{
return y1-((y2-y1)/(x2-x1))*x1;
}
int main()
{
freopen("in1.txt","r",stdin);
int t;
int i;
double a;
double b;
double sum=0;
cin>>t;
while(t--)
{
sum=0;
for(i=0;i<3;i++)
{
cin>>po[i].x>>po[i].y;
}
a=find_a(po[1].x,po[1].y,po[0].x,po[0].y);
//cout<<"a="<<a<<endl;
b=find_b(po[1].x,po[1].y,po[2].x,po[2].y);
//cout<<"b="<<b<<endl;
//cout<<"k="<<((po[1].y-po[2].y)/(po[1].x-po[2].x))<<endl;;
int num=(int)(po[1].x-po[2].x)+1;
double  delt=1.0/1000;
double y;
int c=0;
for(double pos=po[1].x;pos<=po[2].x;)
{
if(a<0)
{
y=(a*(pos-po[0].x)*(pos-po[0].x)+po[0].y)-(((po[1].y-po[2].y)/(po[1].x-po[2].x))*pos+b);
sum+=y*delt;
pos+=delt;
c++;
if(c==1000)
{
c=0;
//cout<<"x="<<pos<<",y1="<<(a*(pos-po[0].x)*(pos-po[0].x)+po[0].y)<<",y2="<<(((po[1].y-po[2].y)/(po[1].x-po[2].x))*pos+b)<<endl;
}
}
else
{
y=(((po[1].y-po[2].y)/(po[1].x-po[2].x))*pos+b)-(a*(pos-po[0].x)*(pos-po[0].x)+po[0].y);
sum+=y*delt;
pos+=delt;
}
}
printf("%.2lf\n",sum);


}
return 0;
}