This figure shows a graph of time at which an object enters a room on the bottom axis and room number on the vertical axis. It shows the room number of an object as a function of time. When the object started from room 1 at time 1, it reached room 5 at time 5, as expected. When the object started from room 1 at time 6, it failed to reach room 5 at time 11; it reached room 5 at time 12. When the object started from room 1 at 23, it failed to reach room 5 at time 28; it reached room 5 at time 30.