import sys
def side(p1, p2, p3): return (p3[1]-p1[1])*(p2[0]-p1[0])-(p2[1]-p1[1])*(p3[0]-p1[0])>0
 
for s in sys.stdin:
  x = map(float, raw_input().split())
  p1 = x[0:2]
  p2 = x[2:4]
  p3 = x[4:6]
  p0 = x[6:]
  print ["NO","YES"][(side(p1, p2, p0)==side(p2, p3, p0) and side(p2, p3, p0)==side(p3, p1, p0))]