Dirty rooms

int N; // total rooms
volatile Room rooms[1..N]
int nextDirtyRoomNumber = 1
int nextDirtyRoomNumbers[1..N]

foreach i in [1..N]:
nextDirtyRoomNumbers[i] = i + 1

while true:
sleep 1 minute
nextDirtyRoomNumber = checkRooms(nextDirtyRoomNumber)
if nextDirtyRoomNumber == N
break
i = nextDirtyRoomNumber
dirty_room_number = []
do
dirty_room_number.append(i)
i = nextDirtyRoomNumbers[i]
while i < N
send dirty_room_number
send 'all clean'

function checkRoomsReturnNextDirtyRoomNumber(startNumber):
if startNumber == N:
return N
nextRoomToCheck = nextDirtyRoomNumbers[startNumber]
if rooms[startNumber].dirty:
nextDirtyRoomNumbers[startNumber] = checkRoomsReturnNextDirtyRoomNumber(nextRoomToCheck)
return startNumber
return checkRoomsReturnNextDirtyRoomNumber[nextRoomToCheck)