1.13. Reflection Point

Given two points $P(p_x, p_y)$ and $Q(q_x, q_y)$ in the two-dimensional plane, we name the point that is in the middle of the two points the mid point, $M(m_x,m_y)$, and the point that is the 180° rotation of $P$ around $Q$ the reflection point, $R(r_x,r_y)$.

Consider the following case:

Given $P(1,1)$ and $Q(3,3)$, we say the mid point $M$ is $M(2,2)$ and the reflection point $R$ is $R(5,5)$. It can be seen from the figure that, $Q$ is the mid-point of $P$ and $R$, so the distance from $P$ to $Q$ and the distance from $Q$ to $R$ are the same.

Write a program that takes 4 integers as input from the user, the coordinates of $P$ and $Q$ (in the order :math:`p_x, p_y, q_x, q_y`), and prints their mid point and the reflection point in the order $m_x, m_y, r_x, r_y$ as floats with 2 digits after the decimal point.

Sample I/O:

Input:
1
1
3
3

Output:
2.00
2.00
5.00
5.00

Input:
-1
-1
1
1

Output:
0.00
0.00
3.00
3.00

Input:
4
5
1
2

Output:
2.50
3.50
-2.00
-1.00

Show the Answer

px = int(input())
py = int(input())
qx = int(input())
qy = int(input())

mx = (px + qx) / 2
my = (py + qy)/2

rx = qx + (qx - px)
ry = qy + (qy - py)

print("{:.2f}".format(mx))
print("{:.2f}".format(my))
print("{:.2f}".format(rx))
print("{:.2f}".format(ry))