101113: [AtCoder]ABC111 D - Robot Arms
Description
Score : $600$ points
Problem Statement
Snuke is introducing a robot arm with the following properties to his factory:
- The robot arm consists of $m$ sections and $m+1$ joints. The sections are numbered $1$, $2$, ..., $m$, and the joints are numbered $0$, $1$, ..., $m$. Section $i$ connects Joint $i-1$ and Joint $i$. The length of Section $i$ is $d_i$.
- For each section, its mode can be specified individually. There are four modes:
L
,R
,D
andU
. The mode of a section decides the direction of that section. If we consider the factory as a coordinate plane, the position of Joint $i$ will be determined as follows (we denote its coordinates as $(x_i, y_i)$):- $(x_0, y_0) = (0, 0)$.
- If the mode of Section $i$ is
L
, $(x_{i}, y_{i}) = (x_{i-1} - d_{i}, y_{i-1})$. - If the mode of Section $i$ is
R
, $(x_{i}, y_{i}) = (x_{i-1} + d_{i}, y_{i-1})$. - If the mode of Section $i$ is
D
, $(x_{i}, y_{i}) = (x_{i-1}, y_{i-1} - d_{i})$. - If the mode of Section $i$ is
U
, $(x_{i}, y_{i}) = (x_{i-1}, y_{i-1} + d_{i})$.
Snuke would like to introduce a robot arm so that the position of Joint $m$ can be matched with all of the $N$ points $(X_1, Y_1), (X_2, Y_2), ..., (X_N, Y_N)$ by properly specifying the modes of the sections. Is this possible? If so, find such a robot arm and how to bring Joint $m$ to each point $(X_j, Y_j)$.
Constraints
- All values in input are integers.
- $1 \leq N \leq 1000$
- $-10^9 \leq X_i \leq 10^9$
- $-10^9 \leq Y_i \leq 10^9$
Partial Score
- In the test cases worth $300$ points, $-10 \leq X_i \leq 10$ and $-10 \leq Y_i \leq 10$ hold.
Input
Input is given from Standard Input in the following format:
$N$ $X_1$ $Y_1$ $X_2$ $Y_2$ $:$ $X_N$ $Y_N$
Output
If the condition can be satisfied, follow the following format. If the condition cannot be satisfied, print -1
.
$m$ $d_1$ $d_2$ $...$ $d_m$ $w_1$ $w_2$ $:$ $w_N$
$m$ and $d_i$ are the configurations of the robot arm. Refer to the problem statement for what each of them means. Here, $1 \leq m \leq 40$ and $1 \leq d_i \leq 10^{12}$ must hold. Also, $m$ and $d_i$ must all be integers.
$w_j$ is a string of length $m$ that represents the way to bring Joint $m$ of the robot arm to point $(X_j, Y_j)$.
The $i$-th character of $w_j$ should be one of the letters L
, R
, D
and U
, representing the mode of Section $i$.
Sample Input 1
3 -1 0 0 3 2 -1
Sample Output 1
2 1 2 RL UU DR
In the given way to bring Joint $m$ of the robot arm to each $(X_j, Y_j)$, the positions of the joints will be as follows:
- To $(X_1, Y_1) = (-1, 0)$: First, the position of Joint $0$ is $(x_0, y_0) = (0, 0)$. As the mode of Section $1$ is
R
, the position of Joint $1$ is $(x_1, y_1) = (1, 0)$. Then, as the mode of Section $2$ isL
, the position of Joint $2$ is $(x_2, y_2) = (-1, 0)$. - To $(X_2, Y_2) = (0, 3)$: $(x_0, y_0) = (0, 0), (x_1, y_1) = (0, 1), (x_2, y_2) = (0, 3)$.
- To $(X_3, Y_3) = (2, -1)$: $(x_0, y_0) = (0, 0), (x_1, y_1) = (0, -1), (x_2, y_2) = (2, -1)$.
Sample Input 2
5 0 0 1 0 2 0 3 0 4 0
Sample Output 2
-1
Sample Input 3
2 1 1 1 1
Sample Output 3
2 1 1 RU UR
There may be duplicated points among $(X_j, Y_j)$.
Sample Input 4
3 -7 -3 7 3 -3 -7
Sample Output 4
5 3 1 4 1 5 LRDUL RDULR DULRD