10899 - Billiard again

[artem]

Please help me.
I have some questions about this problem.

Code: Select all

1 Whats means this sentence "Before the first bounce, the ball increases its distance from the lower left corner of the table."
2 Initinally ball have coordinantes (a/2,b/2) (i think this coord of middle of table)?
3 
(0,b)                              (a,b)
----------------------------------
|           90 degrees           |
|                 |              |
|                 |              |
|   180 degrees -- -- 0 degrees  |
|                 |              |
|                 |              |
|            270 degrees         |
----------------------------------
(0,0)                              (a,0)

This image is right?

[Martin Macko]

2 Initinally ball have coordinantes (a/2,b/2) (i think this coord of middle of table)?

Yes. (Watch the division if a or b is odd.)

3

Code: Select all

(0,b)                              (a,b)
----------------------------------
|           90 degrees           |
|                 |              |
|                 |              |
|   180 degrees -- -- 0 degrees  |
|                 |              |
|                 |              |
|            270 degrees         |
----------------------------------
(0,0)                              (a,0)

This image is right?

Yes, it is

1 Whats means this sentence "Before the first bounce, the ball increases its distance from the lower left corner of the table."

As the initial angle is between 0 and 90 degrees, the ball will go up and/or right from the middle of the table. Thus increasing its distance from lower left (0,0) corner.

[artem]

Thank you very much Martin, i found my logical mistake (i think that length of path of ball is s*v, but i mistaken, length of path of ball is s*v/2) and got AC.