I get WA #8 and I suppose it's because of the precision. I tried rotating everything so that the mirror becomes (0,0) -> (L,0) actually using sin and cos and got WA #8. I tried finding out the relative coordonates without actually using rotations (using distances) and got WA at even lower tests (4 or 5). Can anybody help me with some hints? Should i try it in pascal with the extended type? Or anybody that got AC in C please help.