09 Sept 2026•Go / Python / TypeScript•Easy

Valid Boomerang

Check whether three two-dimensional points are distinct and non-collinear.

Compute the cross product of the two vectors from the first point; a nonzero value means the triangle has positive area.

complexity

O(1) time and O(1) space.

solution files

Go valid-boomerang/solution.go
Python valid-boomerang/solution.py
TypeScript valid-boomerang/solution.ts

Solution files

Go•valid-boomerang/solution.go

package main

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

Python•valid-boomerang/solution.py

class Solution:
    def isBoomerang(self, points: list[list[int]]) -> bool:
        return (points[class="syntax-number">1][class="syntax-number">0] - points[class="syntax-number">0][class="syntax-number">0]) * (points[class="syntax-number">2][class="syntax-number">1] - points[class="syntax-number">0][class="syntax-number">1]) != (points[class="syntax-number">1][class="syntax-number">1] - points[class="syntax-number">0][class="syntax-number">1]) * (points[class="syntax-number">2][class="syntax-number">0] - points[class="syntax-number">0][class="syntax-number">0])

TypeScript•valid-boomerang/solution.ts

function isBoomerang(points: number[][]): boolean {
  return (points[class="syntax-number">1][class="syntax-number">0] - points[class="syntax-number">0][class="syntax-number">0]) * (points[class="syntax-number">2][class="syntax-number">1] - points[class="syntax-number">0][class="syntax-number">1]) !== (points[class="syntax-number">1][class="syntax-number">1] - points[class="syntax-number">0][class="syntax-number">1]) * (points[class="syntax-number">2][class="syntax-number">0] - points[class="syntax-number">0][class="syntax-number">0]);
}