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

int main()
{
	double x1, x2, x3, y1, y2, y3, xp, yp;
	while (cin >> x1 >> y1 >> x2 >> y2 >> x3 >> y3 >> xp >> yp){
		vector<bool> vec(3, true);
		if (x1 * y2 - y1 * x2 < 0) vec[0] = false;
		if (x2 * y3 - y2 * x3 < 0) vec[1] = false;
		if (x3 * y1 - y3 * x1 < 0) vec[2] = false;
		if (vec[0] * vec[1] * vec[2] || !(vec[0] + vec[1] + vec[2])) cout << "YES\n";
		else cout << "NO\n";
	}
	cout.flush();
}