#!/bin/python3

import sys

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

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)