#!/bin/python3

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    if i_start >= n or j_start >= n or i_end >= n or  j_end >= n: return []
    if i_start < 0 or j_start < 0 or i_end < 0 or  j_end < 0: return []
    if i_start == i_end and j_start == j_end: return []
    if (i_start == i_end):
        if abs(j_end - j_start) % 2 != 0: return []
        else:
            if j_start < j_end:
                return ["R"] + printShortestPath(n, i_start, j_start + 2, i_end, j_end)
            elif j_start > j_end:
                return ["L"] + printShortestPath(n, i_start, j_start - 2, i_end, j_end)
    elif (j_start == j_end):
        if abs(i_end - i_start) % 4 != 0: return []
        else:
            l = []
            if i_start < i_end:
                for i in range((i_end - i_start) // 4): l += ["LR", "LL"]
            else:
                for i in range((i_end - i_start) // 4): l += ["UR", "UL"]
            return l
    else:
        if abs(i_end - i_start) % 2 != 0 : return []
        elif (abs(i_end - i_start) // 2 + abs(j_end - j_start)) % 2 != 0: return []
        else:
            if i_end > i_start and j_end > j_start:
                return ["LR"] + printShortestPath(n, i_start + 2, j_start + 1, i_end, j_end)
            elif i_end > i_start and j_end < j_start:
                return ["LL"] + printShortestPath(n, i_start + 2, j_start - 1, i_end, j_end)
            elif i_end < i_start and j_end > j_start:
                return ["UR"] + printShortestPath(n, i_start - 2, j_start + 1, i_end, j_end)
            elif i_end < i_start and j_end < j_start:
                return ["UL"] + printShortestPath(n, i_start - 2, j_start - 1, i_end, j_end)
            return []

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)]
    l = printShortestPath(n, i_start, j_start, i_end, j_end)
    if len(l) == 0: print("Impossible")
    else:
        print(len(l))
        print(*l, sep = ' ')