#!/bin/python3

from collections import deque
import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    iDiff, jDiff = i_end - i_start, j_end - j_start
    if iDiff % 2 == 1 or (iDiff / 2 - jDiff) % 2 == 1:
        print("Impossible")
    else:
        actions, leftTemp = deque(), deque()
        while (iDiff, jDiff) != (0, 0):
            if iDiff == 0:
                for i in range(0, abs(jDiff), 2):
                    if jDiff > 0:
                        actions.append("R")
                    else:
                        actions.append("L")
                break
            elif iDiff < 0:
                while iDiff != 0 and jDiff != 0:
                    if jDiff < 0:
                        iDiff, jDiff = iDiff + 2, jDiff + 1
                        actions.append("UL")
                    else:
                        iDiff, jDiff = iDiff + 2, jDiff - 1
                        actions.append("UR")
                if jDiff == 0:
                    for i in range(0, abs(iDiff), 4):
                        actions.appendleft("UL")
                        actions.append("UR")
            else:
                surplus = abs(jDiff) - int(abs(iDiff) / 2)
                for i in range(0, max(surplus, 0), 2):
                    if jDiff > 0:
                        jDiff -= 2
                        actions.append("R")
                    else:
                        jDiff += 2
                        leftTemp.append("L")
                for i in range(abs(jDiff)):
                    if jDiff < 0:
                        leftTemp.appendleft("LL")
                    else:
                        actions.append("LR")
                iDiff -= 2 * abs(jDiff)
                for i in range(0, abs(iDiff), 4):
                    actions.append("LR")
                for i in range(0, abs(iDiff), 4):
                    actions.append("LL")
                break
        actions = actions + leftTemp
        print(len(actions))
        print(' '.join(actions))
    return

if __name__ == "__main__":
    n = int(input().strip())
    i_start, j_start, i_end, j_end = 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)