How did Ahmed take revenge of Maryia's refusal to him?

 He gathered his friends and got inside her exam hall when it was the break. She was out as well as her exam hall mates.

Ahmed searched for Maryia's seat number, found it, then ordered his friends to put ALL THE DESKS in the hall on hers.

They finished and the bell rang. They ran quickly out of the hall leaving their mess until Maryia comes.

 #The_Track_Of_The_Eyelids

Find out more: https://m.imdb.com/title/tt31079386/