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])
}