An evil-doer got into a depository where gold and platinum bars were stored and
took out n sacks with bars. In each sack there were k bars and all the bars
in each sack were made of the same metal. To arouse less suspicions, the
criminal painted all the bars black, which made gold bars and platinum bars
look the same.
Soon he found a buyer for the platinum bars. However, it turned out that the
thief didn't know which bars were in which sack. Still, he kept his head
and decided to find that out using a balance that could show exact weights. The
thief knew that the mass of a gold bar was x kilograms and the mass of a
platinum bar was y kilograms. Help the thief determine in one weighing in
which sacks there are gold bars and in which sacks there are platinum bars.
Tell him how many bars from each sack he should put on the balance in order to
determine which sacks contain platinum bars.
The only input line contains space-separated integers n, k, x, and y
(3 ≤ n ≤ 20; 1 ≤ k ≤ 106; 1 ≤ x < y ≤ 10).
If it is possible to determine in which sacks there are platinum bars
in one weighing, output “YES” in the first line and output n space-separated integers in
the second line. These numbers must describe how many bars from each sack
should be put on the balance. If there are
several solutions, output any of them. If there is no solution, output
“NO” in the only line.
4 8 9 10
4 5 6 8
Problem Author: Alexander Ipatov (idea by Artyom Skrobov)
Problem Source: XIV Open USU Championship