Given four different points in space. Find whether these points can form a square or not.

Example 1:
Input:
x1 = 20, y1 = 10, x2 = 10, y2 = 20,
x3 = 20, y3 = 20, x4 = 10, y4 = 10
Output:
Yes
Explanation:
The points (20,10), (10,20), (20,20),
(10,10) forms a square.
Example 2:
Input:
x1 = 2, y1 = 1, x2 = 10, y2 = 20,
x3 = 5, y3 = 6, x4 = 10, y4 = 10
Output:
No
Explanation:
The points (2,1), (10,20), (5,6),
(10,10) doesn't form a square.

Your Task:
You don't need to read input or print anything. Your task is to complete the function isSquare() which takes 8 Integers x1, y1, x2, y2, x3, y3, x4, and y4 as input and returns whether these points form a square.

Expected Time Complexity: O(1)
Expected Auxiliary Space: O(1)

Constraints:
-10^{3} ≤ x1, y1, x2, y2, x3, y3, x4, y4 ≤ 10^{3}

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