#!/bin/python3
import sys
komutlist = []
def printShortestPath(n, i_start, j_start, i_end, j_end):
    if (i_start - i_end)%2 != 0:
        print("Impossible")
    else :
        while i_start != i_end or j_start!= j_end:
            if i_start - i_end>0 and j_start - j_end >=0:
                komutlist.append("UL")
                i_start-=2
                j_start-=1
            elif i_start-i_end <0 and j_start - j_end <=0:
                komutlist.append("LR")
                i_start+=2
                j_start+=1
            elif i_start-i_end >0 and j_start - j_end <0:
                komutlist.append("UR")
                i_start-=2
                j_start+=1
            elif i_start-i_end <0 and j_start - j_end >0:
                komutlist.append("LL")
                i_start+=2
                j_start-=1
            elif i_start-i_end==0 and j_start - j_end >0:
                komutlist.append("L")
                j_start-=2
            elif i_start-i_end==0 and j_start - j_end <0:
                komutlist.append("R")
                j_start+=2               
        print(len(komutlist))
        print(*komutlist)
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)