#include <bits/stdc++.h>
using namespace std;
double mod(int x){
    if (x<0){
        x=-x;
    }
    return x;
}
int sign(int x){
    if (x>0){
        return 1;
    }
    if (x==0){
        return 0;
    }
    return -1;
}
struct Point{
    int x;
    int y;
};
Point draw_vector(Point p, Point q){
    return {q.x-p.x, q.y-p.y};
}
int cross_product(Point p, Point q){
    return p.x*q.x+p.y*q.y;
}
int dot_product(Point p, Point q){
    return p.x*q.y-p.y*q.x;
}
int main(){
    Point a, o, b, p;
    cin>>a.x>>a.y>>o.x>>o.y>>b.x>>b.y>>p.x>>p.y;
    if (dot_product(draw_vector(o, a), draw_vector(o, p))==0){
        if (cross_product(draw_vector(o, p), draw_vector(o, a))>=0){
            cout<<"YES"<<"\n";
            return 0;
        }
        cout<<"NO"<<"\n";
        return 0;
    }
    if (dot_product(draw_vector(o, b), draw_vector(o, p))==0){
        if (cross_product(draw_vector(o, p), draw_vector(o, b))>=0){
            cout<<"YES"<<"\n";
            return 0;
        }
        cout<<"NO"<<"\n";
        return 0;
    }
    if (sign(dot_product(draw_vector(o, a), draw_vector(o, p)))==sign(dot_product(draw_vector(o, a), draw_vector(o, b)))){
        if (sign(dot_product(draw_vector(o, b), draw_vector(o, p)))==sign(dot_product(draw_vector(o, b), draw_vector(o, a)))){
            cout<<"YES"<<"\n";
            return 0;
        }
    }
    cout<<"NO"<<"\n";
    return 0;
}