#!/bin/python3

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    #  Print the distance along with the sequence of moves.
    moves = 0
    res = []
    if (i_end - i_start) % 2 != 0:
        print('Impossible')
        return res
    else:
        iturns = int((i_end - i_start) / 2)
        if (abs(j_end - j_start) - abs(iturns)) % 2 != 0:
            print('Impossible')
            return res
        else: # definitely has a solution
            i_curr = i_start
            j_curr = j_start
            while(i_curr != i_end or j_curr != j_end):
                moves += 1
                if i_curr > i_end:
                    i_curr -= 2
                    if (j_curr >= j_end-int((i_curr-i_end)/2-1)) and j_curr > 0: # UL priors to UR
                        res.append('UL')
                        j_curr -= 1
                    else: #j_curr < j_end or j_curr == 0: 
                        res.append('UR')
                        j_curr += 1
                elif i_curr <= i_end and j_curr < j_end-1-int((i_end-i_curr)/2): # R priors to LL/LR/L 
                    j_curr += 2
                    res.append('R')
                elif i_curr < i_end:
                    i_curr += 2
                    if j_curr <= j_end+int((i_end-i_curr)/2) and j_curr < n-1: # LR priors to LL
                        res.append('LR')
                        j_curr += 1
                    else: # j_curr > j_end or j_curr == n-1
                        res.append('LL')
                        j_curr -= 1
                else: #i_curr == i_end and j_curr > j_end:
                    j_curr -= 2
                    res.append('L')
            print(moves)
            print(' '.join(res))
            return res

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)