variable selection screen(urgent)

Hi gurus ,

can any plz help me in this regard.

-- Given the inputs in the variable screen and executed and finally displayed the result area. that's fine.....

But upon refresh iam getting the same previous input values in the variable screen.

-- Upon refresh we need blank(with no previous input values) in the variable screen.

So how can i get this,plz help me

Regards,

Rambo.