UVa-191 :Intersection

#include<iostream>
#include<algorithm>
using namespace std;


class Point{

public:
int x,y;
void input(int a,int b);

};


void Point:: input(int a,int b)
{  x=a;
   y=b;

return ;
}

int cross(Point pi,Point pj,Point pk)
{  int a,b;
//cout<<"calling cross"<<endl;
    a=(pk.x-pi.x)*(pj.y-pi.y);
    b=(pj.x-pi.x)*(pk.y-pi.y);
    return a-b;

}

bool onsegment(Point pi,Point pj,Point pk)
{
    int minx=min(pi.x,pj.x),maxx=max(pi.x,pj.x),miny=min(pi.y,pj.y),maxy=max(pi.y,pj.y);

    if((minx<=pk.x) && (pk.x<=maxx) && (miny<=pk.y) && (pk.y<=maxy)) return true;
    //cout<<minx<<maxx<<maxy<<miny;
    //if(minx<=pk.x &(pk.x<=maxx) )return true;
    else return false;


}
bool intersect(Point P1,Point P2,Point P3,Point P4)
 {   long int d1,d2,d3,d4;
    d1=cross(P3,P4,P1);
    //cout<<"d1"<<d1<<endl;

    d2=cross(P3,P4,P2);
    //cout<<"d2"<<d2<<endl;

    d3=cross(P1,P2,P3);
    //cout<<"d3"<<d3<<endl;
    d4=cross(P1,P2,P4);
    //cout<<"d4"<<d4<<endl;
    if(((d1>0&&d2<0) || (d1<0&&d2>0) )&& ((d3>0&&d4<0)||(d3<0&&d4>0))) return true;
    else if (d1==0 && onsegment(P3,P4,P1)) return true;
    else if(d2==0 && onsegment(P3,P4,P2))return true;
     else if(d3==0 && onsegment(P1,P2,P3))return true;
    else if(d4==0 &&onsegment(P1,P2,P4))return true;

    else return false;}

bool onrect(int ax,int ay,int bx,int by,int Px,int Qy,int Rx,int Sy)
{  bool AX,AY,BX,BY;
  AX=AY=BX=BY=false;
     if(min(Px,Rx)<ax && ax<max(Px,Rx))AX=true;
     if(min(Qy,Sy)<ay &&ay<max(Qy,Sy))AY=true;
      if(min(Px,Rx)<bx && bx<max(Px,Rx))BX=true;
     if(min(Qy,Sy)<by &&by<max(Qy,Sy))BY=true;
     if(AX && AY && BX && BY==true)return true;
     else return false;

}

int main()
{  int tc,t=0;
cin>>tc;
    while(tc--){
    Point Ple,Pbe,P1,P2,P3,P4;
    int xle,yle,xbe,ybe,xleft,ytop,xright,ybottom;
    cin>>xle>>yle>>xbe>>ybe>>xleft>>ytop>>xright>>ybottom;
    bool b=onrect(xle,yle,xbe,ybe,xleft,ytop,xright,ybottom);

    Ple.input(xle,yle);
    Pbe.input(xbe,ybe);

     P1.input(xleft,ytop);
    P2.input(xleft,ybottom);
    P3.input(xright,ybottom);
    P4.input(xright,ytop);
   if(intersect(Ple,Pbe,P1,P2)==true)cout<<"T"<<endl;
   else if(intersect(Ple,Pbe,P2,P3)==true)cout<<"T"<<endl;
      else if (intersect(Ple,Pbe,P3,P4)==true)cout<<"T"<<endl;
   else if(intersect(Ple,Pbe,P4,P1)==true)cout<<"T"<<endl;
   else if(b==true)cout<<"T"<<endl;
   else cout<<"F"<<endl;
   //cout<<"Case :"<<++t<<endl;
   }

    return 0;
}