:)

Use ternary search.

Can anyone explain this problem? I didn't understand why we have L, I think we don't need it, or what should we find at all. or what does it mean, that the width is zero there.

You gotta find the dependence of your length with the angle.
It looks like two variable formula.

What's mean this problem?

help to solve please this problem on with ++. I will be very grateful! it is possible to write on mail juliauhova@mail.ru

In my opinion the problem statement is quite unclear. Although it is said in it that the book might fall at some point it never does (even if it goes beyond the line where physic laws say it falls). The problem my team was solving during the contest was to determine when the book will fall if it falls (and at what X this would happen), and if it doesn't - what is the furthest point to the left the middle of it can go while sliding over the shelf (the original problem). Please change the statement so other people are not confused by this ambiguity.

Does it mean that we need to calculate the maximal displacement where the center goes even when it falls? And after the book starts falling must we consider that the book just rotates around the edge of the bookshelf? or it slides a little backwards. Some more explanation of the problem text and maybe some hints would be welcomed. Thank you.

L.E. Now I get WA 8. I don't think there is a problem with precision, or something like that. Some more samples to pass this test? Does L have to be used at anything? I believe not since L>H.

L.L.E. My WA 8 was from a division by 2 of an integer variable, which I  assigned to a double variable. The problem was solved when I divided by 2.0

Edited by author 25.03.2010 20:20