Ten computer scientists and ten engineers are on line to buy train tickets
to travel to the tech conference in the nearby city.
each of the computer scientists walk up to the window to purchase their train ticket,
and watch as the engineers combine their money to purchase only one ticket.
"stupid engineers," they say amongst themselves, boarding the train.
soon after departing,
the ticket taker enters the train car.
all ten of the engineers pile into the restroom with their single ticket.
the ticket taker collects each of the computer scientists
tickets and proceeds to the rest room.
seeing that it's occupied,
the ticket taker knocks on the door
and asks for the occupant's ticket.
the engineers slip their ticket from under the door
and the ticket taker moves on.
the computer scientists look at each other in astonishment
that the engineers' plan actually worked.
after the conference,
the ten computer scientists and ten engineers line up again to buy their return tickets.
again, the engineers only buy one ticket,
but this time they watch on as the computer scientists buy zero tickets.
"stupid computer scientists,"
they say amongst themselves, boarding the train.
and again,
the ticket taker enters the train car
and all ten engineers pile into the restroom with their single ticket.
"ticket please",
a computer scientist says,
knocking on the restroom door.
sure enough,
the engineers slide their ticket from under the door
as the computer scientists pile into the adjacent restroom.