import bisect

def activityNotifications(expenditure, d):
    warns = 0
    # Initialize sorted trailing window
    trailing = sorted(expenditure[:d])

    for today in range(d, len(expenditure)):
        # Get median from sorted trailing list
        if d % 2 == 1:
            median = trailing[d // 2]
        else:
            median = (trailing[d // 2] + trailing[d // 2 - 1]) / 2

        if expenditure[today] >= 2 * median:
            warns += 1

        # Slide the window
        # Remove the element going out of the window
        old_value = expenditure[today - d]
        del trailing[bisect.bisect_left(trailing, old_value)]

        # Insert the new value to maintain sorted order
        bisect.insort(trailing, expenditure[today])

    return warns