1037. Valid Boomerang

Problem

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:

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

Problem Summary

A boomerang is defined as a set of three points that are all distinct and not in a straight line. Given a list of three points in the plane, determine whether these points can form a boomerang.

Solution Ideas

• Determine whether the given 3 sets of points can satisfy the boomerang condition.
• Easy problem. Determine whether the slopes of the 2 lines formed by the 3 points are equal. Since calculating the slope involves division and may encounter a denominator of 0, it can be converted into multiplication: cross-multiply and then determine whether they are equal. This avoids having to handle the case where the denominator is 0, and the code is also simplified to one line.

Code

package leetcode

func isBoomerang(points [][]int) bool {
	return (points[0][0]-points[1][0])*(points[0][1]-points[2][1]) != (points[0][0]-points[2][0])*(points[0][1]-points[1][1])
}