Problem 275, does anyone have any trick I/O?

[guma]

I' ve just done the 202 problem and I thought the solution of the 275 would be very easy. I guess I was wrong
All the i/o that i got, wich by the way were only the sample ones, are passing. But the judge keep saying me WA.

What should be the output for something like:

0 5

My program shows:

.0
This expansion terminates.

Is this write? Is there any [other] trick I/O?

Thanks for your time,

and sorry for the bad english.