def largest_stock_payout(stocks):
''' Given a stream of stocks and their values, return the
max stock payout that could be achieved by buying and selling
at any ordered time.
:param stocks: a stream of { 'stock-name': [stock-values] }
:returns: The max payout of the stock stream
'''
return { name: largest_difference(vs)
for name, vs in stocks.items() }
def robot_battery_capacity(coordinates):
''' Given a stream of coordinates for a robot, return
the maximum battery capacity needed to traverse the landscape
if it only takes power to move up in the Z direction and we gain
power by moving down in the Z direction.
:param coordinates: a stream of (x,y,z) coordinates
:returns: The max battery capacity needed to traverse
'''
return largest_difference((z for _,_,z in coordinates))
