There are four students: Binh, Dong,  Cuong took part in excellent student competition.

Their teacher said:

-“Each one of them to reach the first, second, third, or encouraging”She suggested people try to guess. 

- Nam: An, Binh reached second prize, Cuong and Dong reached consolation prize

- Lam: An, Dong , Cuong  have won the first prize;  Binh has won the third prize

- Thanh: Binh has won the first prize, An, Dong and Cuong have won third prizes.

After hearing teacher smiled "Nobody like that you are guessing."

In what position were Cuong and Dong ?