#include<bits/stdc++.h>
using namespace std;
#define el "\n"
#define ll long long
#define ull unsigned long long
#define se second
#define fi first
#define be begin()
#define en end()
#define Faster cin.tie(0); cout.tie(0); ios_base::sync_with_stdio(0);
struct toado
{
    double x,y;
    friend istream& operator >> (istream& in, toado &a)
    {
        in >> a.x >> a.y;
        return in;
    }
};
double Stamgiac(toado a, toado b, toado c)
{
    return fabs(a.x*(b.y - c.y) + b.x*(c.y - a.y) + c.x*(a.y - b.y))/ 2.0;

}
bool check(toado a, toado b, toado c, toado d)
{
    if(Stamgiac(a,b,c) == Stamgiac(a,b,d) + Stamgiac(a,d,c) + Stamgiac(d,b,c)) return true;
    return false;
}
int main()
{
    Faster;
    toado a, b, c, d;
    cin >> a >> b >> c >> d;
    if(check(a,b,c,d)) cout << "Yes";
    else cout << "No";
    return 0;
}
//code by chat gpt