Right-Angled Triangle Function

Adapted from Cambridge International AS & A Level Computer Science (9618), May/June 2024 Paper 21, Question 6.

Write function ISRA() that takes six integers representing the coordinates of three triangle vertices:

(x1, y1), (x2, y2), and (x3, y3).

The function must return TRUE if the triangle is right-angled and FALSE otherwise. Use squared lengths so no square root is needed:

A^2 = B^2 + C^2

Input: Six integers. Output: TRUE or FALSE.

Example:

Input:  0
        0
        3
        0
        0
        4
Output: TRUE