class P:
    def __init__(self,x,y,z):
        self.x=x
        self.y=y
        self.z=z

    def __str__(self):
        return "({}, {}, {})".format(self.x,self.y,self.z)

    def __repr__(self):
        return str(self)

    def __neg__(self):
        return P(-self.x,-self.y,-self.z)

    def __sub__(self,other):
        return P(self.x-other.x,self.y-other.y,self.z-other.z)

    def __mul__(self,other):
        return self.x*other.x+self.y*other.y+self.z*other.z
#================================================
A=P(*tuple(map(int,input().split())))
B=P(*tuple(map(int,input().split())))
C=P(*tuple(map(int,input().split())))
D=P(*tuple(map(int,input().split())))

p=B-A;q=C-A
a=p*p;b=c=p*q;d=q*q
s=(D-A)*p;t=(D-A)*q
det=a*d-b*c

alpha=(d*s-b*t)/det
beta =(-c*s+a*t)/det

print("YES" if 0<=alpha<=1 and 0<=beta<=1 and 0<=alpha+beta<=1 else "NO")