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#!/opt/local/bin/python
#
# See ../README.md
#
#
# Run as python ch-2.py < input-file
#
import fileinput
#
# This determines on which side of the line through (x1, y1) and
# (x2, y2) the origin lies. If > 0, then the origin lies to the left
# of the line, if < 0, the origin lies to the right of the line, if
# = 0, the origin lies on the line.
#
def side (x1, y1, x2, y2):
return (y2 - y1) * x2 - (x2 - x1) * y2
for line in fileinput . input ():
#
# Parse input. We need an explicite conversion from strings to floats
#
x1, y1, x2, y2, x3, y3 = map (lambda f: float (f), line . split ())
#
# Determine where the origin is relative to the three lines
# through the vertices of the triangle. Note we have to go
# in a specific order through the points. (Either clock wise,
# or counter clockwise, as long as we're consistent).
#
s1 = side (x2, y2, x3, y3)
s2 = side (x3, y3, x1, y1)
s3 = side (x1, y1, x2, y2)
#
# If the origin either lies to the left (or on) each of the
# lines, or to the right (or on) each of the lines, the origin
# lies inside the triangle. If not, it does not.
#
if s1 <= 0 and s2 <= 0 and s3 <= 0 or \
s1 >= 0 and s2 >= 0 and s3 >= 0:
print (1)
else:
print (0)
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