#include <bits/stdc++.h>
using namespace std;

typedef long long   signed int LL;
typedef long long unsigned int LU;

#define incID(i, l, r) for(int i = (l)    ; i <  (r); i++)
#define incII(i, l, r) for(int i = (l)    ; i <= (r); i++)
#define decID(i, l, r) for(int i = (r) - 1; i >= (l); i--)
#define decII(i, l, r) for(int i = (r)    ; i >= (l); i--)
#define  inc(i, n) incID(i, 0, n)
#define inc1(i, n) incII(i, 1, n)
#define  dec(i, n) decID(i, 0, n)
#define dec1(i, n) decII(i, 1, n)

#define inII(v, l, r) ((l) <= (v) && (v) <= (r))
#define inID(v, l, r) ((l) <= (v) && (v) <  (r))

#define PB push_back
#define EB emplace_back
#define MP make_pair
#define FI first
#define SE second
#define UB upper_bound
#define LB lower_bound
#define PQ priority_queue

#define  ALL(v)  v.begin(),  v.end()
#define RALL(v) v.rbegin(), v.rend()
#define  FOR(it, v) for(auto it =  v.begin(); it !=  v.end(); ++it)
#define RFOR(it, v) for(auto it = v.rbegin(); it != v.rend(); ++it)

template<typename T> bool   setmin(T & a, T b) { if(b <  a) { a = b; return true; } else { return false; } }
template<typename T> bool   setmax(T & a, T b) { if(b >  a) { a = b; return true; } else { return false; } }
template<typename T> bool setmineq(T & a, T b) { if(b <= a) { a = b; return true; } else { return false; } }
template<typename T> bool setmaxeq(T & a, T b) { if(b >= a) { a = b; return true; } else { return false; } }
template<typename T> T gcd(T a, T b) { return (b == 0 ? a : gcd(b, a % b)); }
template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; }

// ---- ----

// ベクトル v からみて点 p が右側にあれば 1, 左なら -1, 境界なら 0
int dir(int vx, int vy, int px, int py) {
	if(vx < 0) {
		vx *= -1;
		vy *= -1;
		px *= -1;
		py *= -1;
	}
	
	int flag = 1;
	if(px < 0) {
		px *= -1;
		py *= -1;
		flag = -1;
	}
	
	int r = 0;
	if(vx * py <  vy * px) { r =  1; }
	if(vx * py == vy * px) { r =  0; }
	if(vx * py >  vy * px) { r = -1; }
	
	return r * flag;
}

// 点 p が三角形 ABC の内側にあれば 1, 外側なら -1, 境界なら 0
int inTri(int ax, int ay, int bx, int by, int cx, int cy, int px, int py) {
	int ab = dir(bx - ax, by - ay, px - ax, py - ay);
	int bc = dir(cx - bx, cy - by, px - bx, py - by);
	int ac = dir(cx - ax, cy - ay, px - ax, py - ay);
	if(ab == 0 || bc == 0 || ac == 0) { return 0; }
	return (ab != ac && bc != ac ? 1 : -1);
}

int x[5], y[5];

int main() {
	/*
	int ax, ay;
	cin >> ax >> ay;
	decII(py, -12, 12) {
	incII(px, -12, 12) {
		if(px == 0 && py == 0) { printf("+ "); }
		else { printf("%c ", "L*R"[1 + dir(ax, ay, px, py)]); }
	} cout << endl;
	} cout << endl;
	return 0;
	*/
	
	inc(i, 5) { cin >> x[i] >> y[i]; }
	
	bool ans = true;
	inc(i, 5) {
	inc(j, i) {
	inc(k, j) {
		inc(l, 5) {
			if(l == i || l == j || l == k) { continue; }
			int it = inTri(x[i], y[i], x[j], y[j], x[k], y[k], x[l], y[l]);
			ans &= (it == -1);
		}
	}
	}
	}
	
	cout << (ans ? "YES" : "NO") << endl;
	
	return 0;
}