#include <iostream>
using namespace std;
struct Point {
    int x, y;
    Point() {}
};
struct GeomitryVector {
    int x, y;
    GeomitryVector() {}
    GeomitryVector(Point A, Point B) {
        x = A.x - B.x;
        y = A.y - B.y;
    }
    int operator * (GeomitryVector &A) {
        return x * A.y - A.x * y;
    }
};
bool checkPoint(Point a, Point b, Point c, Point d) {
    GeomitryVector f(a, b);
    GeomitryVector s(a, c);
    GeomitryVector t(a, d);
    return((f*s < 0 && f*t < 0) || (f*s > 0 && f*t > 0));
}
int main() {
    Point a, b, c, d;
    cin >> a.x >> a.y >> b.x >> b.y >> c.x >> c.y >> d.x >> d.y;
    if (checkPoint(a, b, c, d)) cout << "Yes";
    else cout << "No";
    return 0;
}