0
$begingroup$
This is the question from a Codility test, as a task in an interview: DeepestPit - problem description A non-empty zero-indexed array A consisting of N integers is given. A pit in this array is any triplet of integers (P, Q, R) such that: · 0 ≤ P < Q < R < N; · sequence [A[P], A[P+1], ..., A[Q]] is strictly decreasing, i.e. A[P] > A[P+1] > ... > A[Q]; · sequence A[Q], A[Q+1], ..., A[R] is strictly increasing, i.e. A[Q] < A[Q+1] < ... < A[R]. The depth of a pit (P, Q, R) is the number min {A[P] − A[Q], A[R] − A[Q]}. For example, consider array A consisting of 10 elements such that: A[0] = 0 A[1] = 1 A[2] = 3 A[3] = -2 A[4] = 0 A[5] = 1 A[6] = 0 A[7] = -3 A[8] = 2 A[9] = 3 Triplet (2, 3, 4) is