protected.

$3.$ The behaviour rules for the medley simulation

These rules are listed in a recommended order of trying to enforce them. Start at the

beginning and work your way through the list.

$1.$ The Start button initiates the simulation $$ no swimmers enter the stadium until this is

pressed.

$2.$ The Quit button terminates the simulation $($it does, this works already$).$

$3.$ Only one swimmer is allowed on a grid position $($GridBlock$)$ at any point in time.

$4.$ Swimmers move block by block and simultaneously to ensure liveness.

$5.$ After the start button is pressed, swimmers enter through the entrance door one at a

time, in the race order of their swim stroke $($e$.$g$.$ Backstroke first$),$ arriving swimmers must

wait if entrance door is occupied.

$6.$ Swimmers line up at the starting blocks for their team in their race order $($order of the

swim stroke$).$

$7.$ The race begins only when the all backstroke swimmers $($the first to swim, black circles in

the simulation$)$ for every team are in place. If other team members have not arrived yet,

that is fine: the race can start. The race starts with the backstroke swimmers swimming to

the end of the pool and back.

$8.$ Other members of the team can only start their leg of the race when their previous team

member has finished their leg $$ this is a relay. So breaststroke waits for backstroke,

butterfly waits for breaststroke and freestyle waits for butterfly.

$9.$ The team with the first freestyle winner home wins the race.