Processing math: 100%

Time Limit : sec, Memory Limit : KB
English / Japanese  

A Point in a Triangle

There is a triangle formed by three points (x1,y1), (x2,y2), (x3,y3) on a plain.

Write a program which prints "YES" if a point P (xp,yp) is in the triangle and "NO" if not.

Input

Input consists of several datasets. Each dataset consists of:

x1 y1 x2 y2 x3 y3 xp yp

All the input are real numbers. Input ends with EOF. The number of datasets is less than or equal to 100.

Constraints

You can assume that:

  • 100x1,y1,x2,y2,x3,y3,xp,yp100
  • 1.0 Length of each side of a tringle
  • 0.001 Distance between P and each side of a triangle

Output

For each dataset, print "YES" or "NO" in a line.

Sample Input

0.0 0.0 2.0 0.0 2.0 2.0 1.5 0.5
0.0 0.0 1.0 4.0 5.0 3.0 -1.0 3.0

Output for the Sample Input

YES
NO

 
BESsBESsBESsBESsBESsBESsBESsBESs