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 CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
const int inf = (int)1e9;
const int mod = inf + 7;
const double pi = acos(-1.0);
const int days[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
long long ax, ay, bx, by, cx, cy;
long long GetDist(long long x, long long y, long long a, long long b) {
  return ((x - a) * (x - a) + (y - b) * (y - b));
}
int main() {
  cin >> ax >> ay >> bx >> by >> cx >> cy;
  if (GetDist(ax, ay, bx, by) == GetDist(bx, by, cx, cy)) {
    if (ax == bx && bx == cx)
      cout << "No";
    else if (ay == by && by == cy)
      cout << "No";
    else if (ax - bx == bx - cx && ay - by == by - cy)
      cout << "No";
    else
      cout << "Yes";
  } else
    cout << "No";
  return 0;
}