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:
def vector_product(v1x, v1y, v2x, v2y):
    return (v1x * v2y - v1y * v2x)

def len_sq(vx, vy):
    return (vx * vx + vy * vy)
    
ax, ay, bx, by, cx, cy = (int(x) for x in input().split())
abx = bx - ax
aby = by - ay
bcx = cx - bx
bcy = cy - by
if vector_product(abx, aby, bcx, bcy) == 0:
    print('No')
elif len_sq(abx, aby) != len_sq(bcx, bcy):
    print('No')
else:
    print('Yes')