Problem: Arpa is taking a geometry exam. Here is the last problem of the exam.

You are given three points a, b, c.

Find a point and an angle such that if we rotate the page around the point by the angle, the new position of a is the same as the old position of b, and the new position of b is the same as the old position of c.

Arpa is doubting if the problem has a solution or not (i.e. if there exists a point and an angle satisfying the condition). Help Arpa determine if the question has a solution or not.

Input

The only line contains six integers ax, ay, bx, by, cx, cy (|ax|, |ay|, |bx|, |by|, |cx|, |cy| ≤ 109). It's guaranteed that the points are distinct.

Output

Print "Yes" if the problem has a solution, "No" otherwise.

You can print each letter in any case (upper or lower).

Examples

Input

0 1 1 1 1 0


Output

Yes


Input

1 1 0 0 1000 1000


Output

No

Note

In the first sample test, rotate the page around (0.5, 0.5) by <image>.

In the second sample test, you can't find any solution.

Solution (in PYTHON3):

Solution:
import math

ax, ay, bx, by, cx, cy = input().split(' ')

ax = int(ax)
ay = int(ay)
bx = int(bx)
by = int(by)
cx = int(cx)
cy = int(cy)

if( ((ax - bx)*(by - cy)) == ((ay - by)*(bx - cx)) ):
    print("No")
    exit()

dist_ab = (ax - bx)**2 + (ay - by)**2

dist_bc = (bx - cx)**2 + (by - cy)**2

if(dist_ab == dist_bc):
    print("Yes")
else:
    print("No")