lost time

Student sleeping in class
Teacher shouts for homework
Which wakes up the student and ask to go to the washroom
The teacher angrily shouts to go ahead
He ends up running out
As he goes out, his teacher slams the door behind him
Runs out
And enters the elevator
Waiting inside the elevator
He finally reaches his floor
An hour, later, he wasted his time
He's rushing to his classroom
running
running
The classroom is lock and his stuff is inside
He gives up