#!/bin/python3

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    mov = []
    if abs(i_end-i_start)%2!=0:
        print("Impossible")
    else:
        if i_end<i_start:
            diff = i_start-i_end
            nom = diff//2
            if j_end>j_start:
                new_j = j_start + nom
                if (j_end-new_j)%2!=0:
                    print("Impossible")
                else:
                    mov = ['UR']*nom
                    hm = (j_end-new_j)//2
                    temp = ['R']*hm
                    mov += temp
                    nom += hm
                    print(nom)
                    print(' '.join(mov))
            elif j_end<j_start:
                new_j = j_start - nom
                if (new_j-j_end)%2!=0:
                    print("Impossible")
                else:
                    mov = ['UL']*nom
                    hm = (new_j-j_end)//2
                    temp = ['L']*hm
                    mov += temp
                    nom += hm
                    print(nom)
                    print(' '.join(mov))
            else:
                if diff%4==0:
                    t = diff//4
                    if (j_start - t)>=0:
                        mov = ['UL']*t
                        mov += ['UR']*t
                        print(len(mov))
                        print(' '.join(mov))
                    else:
                        if j_start == 0:
                            mov = ['UR']*t
                            mov += ['UL']*t
                            print(len(mov))
                            print(' '.join(mov))
                        else:
                            mov = ['UL']*(t-j_start)
                            mov += ['UR']*(t)
                            mov += ['UL']*(j_start)
                            print(len(mov))
                            print(' '.join(mov))
                else:
                    print("Impossible")
        elif i_end>i_start:
            diff = i_end-i_start
            nom = diff//2
            if j_end>j_start:
                new_j = j_start + nom
                if (j_end-new_j)%2!=0:
                    print("Impossible")
                else:
                    mov = ['LR']*nom
                    hm = (j_end-new_j)//2
                    temp = ['R']*hm
                    mov += temp
                    nom += hm
                    print(nom)
                    print(' '.join(mov))
            elif j_end<j_start:
                new_j = j_start - nom
                if (new_j-j_end)%2!=0:
                    print("Impossible")
                else:
                    mov = ['LL']*nom
                    hm = (new_j-j_end)//2
                    temp = ['L']*hm
                    mov += temp
                    nom += hm
                    print(nom)
                    print(' '.join(mov))
            else:
                if diff%4==0:
                    t = diff//4
                    if (j_start + t)<n:
                        mov = ['LR']*t
                        mov += ['LL']*t
                        print(len(mov))
                        print(' '.join(mov))
                    else:
                        if j_start == n-1:
                            mov = ['LL']*t
                            mov += ['LR']*t
                            print(len(mov))
                            print(' '.join(mov))
                        else:
                            mov = ['LR']*(n-1-j_start)
                            mov += ['LL']*(t)
                            mov += ['LR']*(t-n+1+j_start)
                            print(len(mov))
                            print(' '.join(mov))
                else:
                    print("Impossible")
        else:
            if j_end>j_start:
                if (j_end-j_start)%2!=0:
                    print("Impossible")
                else:
                    nom = (j_end-j_start)//2
                    mov = ['R']*nom
                    print(nom)
                    print(' '.join(mov))
            elif j_end<j_start:
                if (j_start-j_end)%2!=0:
                    print("Impossible")
                else:
                    nom = (j_start-j_end)//2
                    mov = ['L']*nom
                    print(nom)
                    print(' '.join(mov))                    

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)