uses crt;
Var
n,i,dem,TC:longint; A:array[0..1000] of longint;
Begin
clrscr;
Repeat
Readln(n);
until n>0; for i:=1 to n do readln(A[i]);
Dem:=0; TC:=0;
For i:=1 to n do if A[i] mod 2=0 then
Begin
TC:=TC+A[i]; dem:=dem+1;
End;
writeln('Trung binh cong so chan: ',TC/dem:2:1);
write('Cac so vua chia het cho 3 vua chia het cho 5: ');
For i:=1 to n do if (A[i] mod 3=0) and (A[i] mod 5=0) then write(i,' ');
Readln;
End.