#!/bin/python

import sys

directions = {(-2, -1): "UL", (-2, 1): "UR", (0, -2): "L",
              (0, 2): "R", (2, -1): "LL", (2, 1): "LR"}

def printShortestPath(n, i_start, j_start, i_end, j_end):
    #  Print the distance along with the sequence of moves.
    deltaI = i_end - i_start
    if deltaI % 2 == 1:
        print("Impossible")
        return
    deltaI2 = deltaI // 2
    deltaJ = j_end - j_start
    if deltaI2 % 2 == 1:
        if (deltaJ % 2) == 0:
            print("Impossible")
            return
    elif (deltaJ % 2) == 1:
        print("Impossible")
        return
    path = []
    # priority UL, UR, R, LR, LL, L
    if abs(deltaI2) <= abs(deltaJ):
        if deltaI2 <= 0:
            if deltaJ <= 0:
                path = ["UL"]*abs(deltaI2) + ["L"]*((abs(deltaJ) - abs(deltaI2))//2)
            else:
                path = ["UR"]*abs(deltaI2) + ["R"]*((abs(deltaJ) - abs(deltaI2))//2)
        elif deltaJ <= 0:
            path = ["LL"]*abs(deltaI2) + ["L"]*((abs(deltaJ) - abs(deltaI2))//2)
        else:
            path = ["R"]*((abs(deltaJ) - abs(deltaI2))//2) + ["LR"]*abs(deltaI2)
    else: # abs(deltaI2) > abs(deltaJ)      
        halfZigZagHeight = (abs(deltaI2) - abs(deltaJ))//2
        maxLeftSteps = j_start
        maxRightSteps = (n - 1 - j_start)
        if deltaI2 <= 0:
            if deltaJ <= 0:
                if abs(deltaJ) + halfZigZagHeight > maxLeftSteps:
                    backAndForth = abs(deltaJ) + halfZigZagHeight - maxLeftSteps
                    path = (["UL"] * maxLeftSteps + ["UR", "UL"] * backAndForth
                            + ["UR"] * (halfZigZagHeight - backAndForth))
                else:
                    path = ["UL"]*(abs(deltaJ)+halfZigZagHeight) + ["UR"]*halfZigZagHeight
            elif halfZigZagHeight > maxLeftSteps:
                    backAndForth = halfZigZagHeight - maxLeftSteps
                    path = (["UL"] * maxLeftSteps + ["UR", "UL"] * backAndForth
                            + ["UR"] * (abs(deltaJ) + halfZigZagHeight - backAndForth))
            else:
                path = ["UL"] * halfZigZagHeight + ["UR"] * (abs(deltaJ) + halfZigZagHeight)
        elif deltaJ >= 0: # deltaI2 > 0
            if abs(deltaJ) + halfZigZagHeight > maxRightSteps:
                backAndForth = abs(deltaJ) + halfZigZagHeight - maxRightSteps
                path = (["LR"] * maxRightSteps + ["LL", "LR"] * backAndForth
                        + ["LL"] * (halfZigZagHeight - backAndForth))
            else:
                path = ["LR"]*(abs(deltaJ)+halfZigZagHeight) + ["LL"]*halfZigZagHeight
        elif halfZigZagHeight > maxRightSteps: # deltaJ > 0 and deltaI2 > 0:
            backAndForth = halfZigZagHeight - maxRightSteps
            path = (["LR"] * maxRightSteps + ["LL", "LR"] * backAndForth
                    + ["LL"] * (abs(deltaJ) + halfZigZagHeight - backAndForth))
        else:
            path = ["LR"] * halfZigZagHeight + ["LL"] * (abs(deltaJ) + halfZigZagHeight)  
    print(len(path))
    print(" ".join(path))

    
if __name__ == "__main__":
    n = int(raw_input().strip())
    i_start, j_start, i_end, j_end = raw_input().strip().split(' ')
    i_start, j_start, i_end, j_end = [int(i_start), int(j_start), int(i_end), int(j_end)]
    printShortestPath(n, i_start, j_start, i_end, j_end)