func abs(n int) int {
	if n < 0 {
		return -n
	}

	return n
}

func arrayMaximalAdjacentDifference(a []int) int {
	diff := 0

	for i := 1; i < len(a)-1; i++ {
		diff = max(diff, abs(a[i]-a[i-1]), abs(a[i]-a[i+1]))
	}

	return diff
}