Valid Boomerang

LeetCode Q 1037 - Valid Boomerang

A boomerang is a set of 3 points that are all distinct and not in a straight line.
Given a list of three points in the plane, return whether these points are a boomerang.

Example 1: Input: [[1,1],[2,3],[3,2]] ; Output: true
Example 2: Input: [[1,1],[2,2],[3,3]] ; Output: false

Note:

• points.length == 3
• points[i].length == 2
• 0 <= points[i][j] <= 100

Solution

Using (x1 - x2)/(y1 - y2) = (x2 - x3)/(y2 - y3) to identify whether three points are in a line. But in the code we need to transfer division to multiplication, otherwise we may encounter java.lang.ArithmeticException: / by zero issue (e.g. input: [[0,0],[1,0],[2,2]]).

Code:

public boolean isBoomerang(int[][] points) {
  int x1 = points[0][0], y1 = points[0][1];
  int x2 = points[1][0], y2 = points[1][1];
  int x3 = points[2][0], y3 = points[2][1];
  
  if ( (x1 == x2 && y1 == y2) || (x2 == x3 && y2 == y3)|| (x1 == x3 && y1 == y3) )
    return false;
  
  if ( (x1 - x2) * (y2 - y3) == (x2 - x3) * (y1 - y2) )
    return false;
  
  return true;
}