regmay

var n,i,m,pp,a:integer;

Begin

pp:=0;

m:=0;

Readln(n);

for i:=1 to n do Begin

Readln(a);

if (pp=0) and (a mod 3=0) then Begin

pp:=1;

m:=a;

end;

if (pp=1) and (a mod 3=0) and (a<m) then m:=a;

end;

Writeln(m);

end.