#!/bin/python3

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    #  Print the distance along with the sequence of moves.
    c=0
    f=1
    a=[]
    i_d = i_start - i_end
    j_d = j_start - j_end
    if(i_d%2 != 0):
        print("Impossible")
    else:
        while(i_d>0):
            if(j_d>=0):
                a.append('UL')
                c+=1
                i_d-=2
                j_d-=1
            elif(j_d<0):
                a.append('UR')
                c+=1
                i_d-=2
                j_d+=1
        while(j_d+2<0 and i_d%2 == 0):
            a.append('R')
            c+=1
            j_d+=2            
        while(i_d<0):
            if(j_d>0):
                a.append('LL')
                c+=1
                i_d+=2
                j_d-=1
            elif(j_d<=0):
                a.append('LR')
                c+=1
                i_d+=2
                j_d+=1
        while(j_d-2>0 and i_d%2 == 0):
            a.append('L')
            c+=1
            j_d-=2
        if(i_d==0 and j_d!=0):
            if(j_d-1>0):
                a.append('L')
                c+=1
                j_d-=2
            elif(j_d+1<0):
                a.append('R')
                c+=1
                j_d+=2
            else:
                f=0
        if(f):
            print(c)
            print(*a)
        else:
            print("Impossible")

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)