#!/usr/bin/env python3
import itertools
cross = lambda a, b: (a.conjugate() * b).imag
ccw = lambda a, b, c: cross(b - a, c - a)
ps = [ complex(*[ int(it) for it in input().split() ]) for _ in range(5) ]
ans = False
for ps in itertools.permutations(ps):
    for i in range(5):
        f = lambda *args: ccw(*[ ps[(i+j)%5] for j in args ])
        if not (f(0, 1, 2) < 0 and f(0, 1, 3) > 0 and f(0, 1, 4) < 0):
           break
    else:
        ans = True
print(['NO','YES'][ans])