package q812

func area2(a, b []int) float64 {
	return float64((a[1]+b[1])*(b[0]-a[0])) / 2
}

func largestTriangleArea(points [][]int) float64 {
	var maxArea float64

	for a := 0; a < len(points)-2; a++ {
		for b := a + 1; b < len(points)-1; b++ {
			for c := b + 1; c < len(points); c++ {
				area := area2(points[a], points[b]) + area2(points[b], points[c]) + area2(points[c], points[a])
				if area < 0 {
					area = -area
				}
				maxArea = max(maxArea, area)
			}
		}
	}
	return maxArea
}

var _ = largestTriangleArea