import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

import numpy as np

data = np.array(read().split(), np.int64)

A,B,C,D = [data[3*i:3*i+3] for i in range(4)]

def test(A,B,C,D):
    v = np.cross(B-A, C-A)
    n = np.cross(B-A, v)
    return np.sign(np.dot(n,C-A)) == np.sign(np.dot(n,D-A))

bl = True
for _ in range(3):
    A,B,C = B,C,A
    bl &= test(A,B,C,D)

answer = 'YES' if bl else 'NO'
print(answer)