Var a,sum,count:integer;
Begin
Repeat
Read(a);
If a mod 9=0 then begin
Count:=count+1;
Sum:=sum+a;
End;
Until a=0
If sum = 0 then write('no')
Else write(sum/count);
End.
Var a,sum,count:integer;
Begin
Repeat
Read(a);
If a mod 9=0 then begin
Count:=count+1;
Sum:=sum+a;
End;
Until a=0
If sum = 0 then write('no')
Else write(sum/count);
End.