#!/bin/python3

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    result=[]
    if (i_start-i_end)%2!=0:
        print("Impossible")
    else:
        while True:
            if i_start==i_end and j_start==j_end:
                break
            elif i_start-i_end>0 and j_start-j_end>=0:
                result.append("UL")
                i_start-=2
                j_start-=1
            elif i_start-i_end<0 and j_start-j_end<=0:
                result.append("LR")
                i_start+=2
                j_start+=1
            elif i_start-i_end>0 and j_start-j_end<0:
                result.append("UR")
                i_start-=2
                j_start+=1
            elif i_start-i_end<0 and j_start-j_end>0:
                result.append("LL")
                i_start+=2
                j_start-=1
            elif i_start-i_end==0 and j_start-j_end>0:
                result.append("L")
                j_start-=2
            elif i_start-i_end==0 and j_start-j_end<0:
                result.append("R")
                j_start+=2
        print(len(result))
        print(*result)

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)