function problem_e(id, pr, n, a):
    i := id
    s := 0

    while i < n:
        for j := 0 until i:
            if a[j] > a[i]:
                s += 1
        i += pr

    left := 2 * id + 1
    right := left + 1

    if left < pr:
        s += receive(left)
    if right < pr:
        s += receive(right)

    if id != 0:
        send((id - 1) / 2, s)
    else:
        print(s)