#!/bin/python

import sys

def impossible(i_diff, j_diff):
  if (i_diff % 2 != 0) or (j_diff % 2 == 0 and i_diff % 4 != 0) or (j_diff % 2 != 0 and (i_diff % 2 != 0 or i_diff == 0)):
    return True

def possible(i_diff, j_diff):
  if j_diff == 0:
    vertical_line(i_diff)
  elif j_diff < 0:
    left(i_diff, j_diff)
  else:
    right(i_diff, j_diff)

def vertical_line(i_diff):
  global moves
  global path
  m = abs(i_diff // 4)
  if i_diff > 0:
    path += "LR LL " * m
  else:
    path += "UL UR " * m
  moves += m*2

def left(i_diff, j_diff):
  global moves
  global path
  if i_diff == 0:
    m = abs(j_diff // 2)
    path += "L "* m
    moves += m
  else:
    path += "UL " if i_diff < 0 else "LL "
    moves += 1
    i_diff = i_diff-1 if i_diff > 0 else i_diff+1
    j_diff = j_diff-2 if j_diff > 0 else j_diff+2
    possible(i_diff, j_diff)

def right(i_diff, j_diff):
  global moves
  global path
  if i_diff == 0:
    m = abs(j_diff // 2)
    path += "R "* m
    moves += m
  else:
    path += "UR " if i_diff < 0 else "LR "
    moves += 1
    i_diff = i_diff-1 if i_diff > 0 else i_diff+1
    j_diff = j_diff-2 if j_diff > 0 else j_diff+2
    possible(i_diff, j_diff)
    
def printShortestPath(n, i_start, j_start, i_end, j_end):
    i_diff = i_end - i_start
    j_diff = j_end - j_start
    if impossible(abs(i_diff), abs(j_diff)):
      print("Impossible")
    else:
      global moves
      global path
      moves = 0
      path = ""
      possible(i_diff, j_diff)
      print(moves)
      print(path.strip())

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)