Problem Statement
Consider an infinite two-dimensional coordinate plane. Takahashi, who is initially standing at $(0,0)$, will do $N$ jumps in one of the four directions he chooses every time: up, down, left, or right. The length of each jump is fixed. Specifically, the $i$-th jump should cover the distance of $D_i$. Determine whether it is possible to be exactly at $(A, B)$ after $N$ jumps. If it is possible, show one way to do so.
Here, for each direction, a jump of length $D$ from $(X, Y)$ takes him to the following point:
- up:
$(X,Y) \to (X,Y+D)$ - down:
$(X,Y) \to (X,Y-D)$ - left:
$(X,Y) \to (X-D,Y)$ - right:
$(X,Y) \to (X+D,Y)$.
Constraints
$1 \leq N \leq 2000$$\lvert A\rvert, \lvert B\rvert \leq 3.6\times 10^6$$1 \leq D_i \leq 1800$- All values in input are integers.
Input
Input is given from Standard Input in the following format:
N A B
D_1 D_2 \ldots D_N
Output
In the first line, print Yes if there is a desired sequence of jumps, and No otherwise.
In the case of Yes, print in the second line a desired sequence of jumps as a string $S$ of length $N$ consisting of U , D , L , R, as follows:
- if the
$i$-th jump is upward, the$i$-th character should beU; - if the
$i$-th jump is downward, the$i$-th character should beD; - if the
$i$-th jump is to the left, the$i$-th character should beL; - if the
$i$-th jump is to the right, the$i$-th character should beR.
样例
3 2 -2
1 2 3
Yes
LDR
2 1 0
1 6
No
5 6 7
1 3 5 7 9
Yes
LRLUR
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