#!/bin/python3

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    #  Print the distance along with the sequence of moves.
    if abs(i_end - i_start) % 2 == 1 or abs(j_end - j_start) % 2 != (abs(i_end - i_start) / 2) % 2:
        print("Impossible")
        return
    re = []
    while i_start > i_end:
        if (i_start - i_end) / 2 > j_end - j_start:
            re.append('UL')
            j_start -= 1
        else:
            re.append('UR')
            j_start += 1
        i_start -= 2
    while j_start < j_end and j_end - j_start > (i_end - i_start) / 2:
        re.append('R')
        j_start += 2           
    while i_end > i_start:
        if (i_end - i_start) / 2 > j_start - j_end:
            re.append('LR')
            j_start += 1
        else:
            re.append('LL')
            j_start -= 1
        i_start += 2
    while j_start > j_end:
        re.append('L')
        j_start -= 2
    print(len(re))
    print(*re)

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)