Description: 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 Format: 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 Format: Print "Yes" if the problem has a solution, "No" otherwise. You can print each letter in any case (upper or lower). Note: In the first sample test, rotate the page around (0.5, 0.5) by $$90^\circ$$. In the second sample test, you can't find any solution.