function fun (x:integer):integer; 
   Begin 
      If x > 100 then fun : x – 10 
      Else fun : fun(fun (x + 11)) 
   End; 

Suppose we have a database consisting of the following three relations.

FREQUENTS (student, parlor) giving the parlors each student visits.

SERVES (parlor, ice-cream) indicating what kind of ice-creams each parlor serves.

LIKES (student, ice-cream) indicating what ice-creams each student likes.

Express the following in SQL:
Print the students that frequent at least one parlor that serves some ice-cream that they like.