#!/bin/python

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    row_diff = abs(i_start - i_end)
    col_diff = abs(j_start - j_end)
    if row_diff % 2 == 1 or (row_diff / 2 + col_diff) % 2 == 1:
        print 'Impossible'
    else:
        ans = []
        while i_start != i_end or j_start != j_end:
            # UL, UR, R, LR, LL, L
            if i_start > i_end and j_start >= j_end and i_start - 2 >= 0 and j_start - 1 >= 0:
                ans.append('UL')
                i_start -= 2
                j_start -= 1
            elif i_start > i_end and j_start < j_end and i_start - 2  >= 0 and j_start + 1 < n:
                ans.append('UR')
                i_start -= 2
                j_start += 1
            elif i_start == i_end and j_start < j_end:
                ans.append('R')
                j_start += 2
            elif i_start < i_end and j_start <= j_end and j_start + 1 < n:
                ans.append('LR')
                i_start += 2
                j_start += 1
            elif i_start < i_end and j_start - 1 >= 0:
                ans.append('LL')
                i_start += 2
                j_start -= 1
            else:
                ans.append('L')
                j_start -= 2
        print len(ans)
        for i in ans:
            print i,

if __name__ == "__main__":
    n = int(raw_input().strip())
    i_start, j_start, i_end, j_end = raw_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)