#P1898C. Colorful Grid
Colorful Grid
Description
Elena has a grid formed by horizontal lines and vertical lines. The horizontal lines are numbered by integers from to from top to bottom. The vertical lines are numbered by integers from to from left to right. For each and (, ), the notation denotes the point at the intersection of the -th horizontal line and -th vertical line.
Two points and are adjacent if and only if .

Elena calls a sequence of points of length a walk if and only if all the following conditions hold:
- The first point in this sequence is .
- The last point in this sequence is .
- For each , the points and are adjacent.
Note that the walk may contain the same point more than once. In particular, it may contain point or multiple times.
There are segments connecting the adjacent points in Elena's grid. Elena wants to color each of these segments in blue or red color so that there exists a walk of length such that
- out of segments connecting two consecutive points in this walk, no two consecutive segments have the same color (in other words, for each , the color of the segment between points and differs from the color of the segment between points and ).
Please find any such coloring or report that there is no such coloring.
Each test contains multiple test cases. The first line contains the number of test cases (). The description of test cases follows.
The only line of each test case contains three integers , , and (, ) — the dimensions of the grid and the number of segments in the walk Elena is looking for.
For each test case, output "NO" if it is not possible to color each of the segments in blue or red color, so that there exists a walk of length satisfying the condition from the statement.
Otherwise, output in the first line "YES", and then provide the required coloring.
In each of the first lines of coloring description, output space-separated characters. The -th character in the -th of these lines should denote the color of the segment between points and . Here, use 'B' to denote the blue color and 'R' to denote the red color.
In each of the next lines of coloring description, output space-separated characters. The -th character in the -th of these lines should denote the color of the segment between points and . Similarly, use 'B' to denote the blue color and 'R' to denote the red color.
You can output each letter in the answer in any case (upper or lower). For example, the strings "yEs", "yes", "Yes", and "YES" will be recognized as positive responses, and both 'R' and 'r' are valid notation of red.
Input
Each test contains multiple test cases. The first line contains the number of test cases (). The description of test cases follows.
The only line of each test case contains three integers , , and (, ) — the dimensions of the grid and the number of segments in the walk Elena is looking for.
Output
For each test case, output "NO" if it is not possible to color each of the segments in blue or red color, so that there exists a walk of length satisfying the condition from the statement.
Otherwise, output in the first line "YES", and then provide the required coloring.
In each of the first lines of coloring description, output space-separated characters. The -th character in the -th of these lines should denote the color of the segment between points and . Here, use 'B' to denote the blue color and 'R' to denote the red color.
In each of the next lines of coloring description, output space-separated characters. The -th character in the -th of these lines should denote the color of the segment between points and . Similarly, use 'B' to denote the blue color and 'R' to denote the red color.
You can output each letter in the answer in any case (upper or lower). For example, the strings "yEs", "yes", "Yes", and "YES" will be recognized as positive responses, and both 'R' and 'r' are valid notation of red.
Note
In the first test case, one of the correct answers is shown in the picture below. The color-alternating walk of length is highlighted.

In the second and the third test cases, it can be shown that there is no coloring satisfying the condition from the statement.