# Internet Problem Solving Contest

## Problem D – Divide the rectangle

Given is a rectangle consisting of r ×c unit squares. One of these squares, in row rr and column cr, is colored red. A different square, in row rb and column cb, is colored blue.

Easy subproblem: Color each of the remaining squares red or blue in such a way that the red part and the blue part have the same shape. (That is, the set of blue squares can be obtained from the set of red squares by using shifts, rotations and reflections.)

Hard subproblem: Color each of the remaining squares red or blue in such a way that the red part has and the blue part have the same shape. Additionally, the red part (and therefore also the blue part) must be connected.

A set of squares S is connected if it is possible to travel between any two of them without leaving S, using horizontal and vertical steps only.

Input specification

The first line of the input file contains an integer t specifying the number of test cases. Each test case is preceded by a blank line.

Each test case consists of three lines. The first line contains the dimensions r and c. The second line contains the coordinates rr and cr. The third line contains the coordinates rb and cb. You may assume that 1 rr,rb r 100, 1 cr,cb c 100, and (rr,cr) (rb,cb).

Output specification

For each test case, output r lines containing c characters each, each of the characters being R (red) or B (blue). If there are multiple solutions, pick any of them. If there is no solution, output one line with the string “IMPOSSIBLE”. You may output empty lines between test cases.

Example

input
3

5 5
1 1
3 4

4 6
1 1
4 6

4 6
1 1
1 2
output
IMPOSSIBLE

RRRRRR
RRRRRB
RBBBBB
BBBBBB

RBBBBB
RBRRRB
RBBBRB
RRRRRB

This output would be correct in both subtasks.