#!/bin/python3

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end, num, steps):
    if abs(i_start - i_end)%2 != 0:
        print("Impossible")
        return
    elif abs(i_start - i_end)%4 == 0 and abs(j_start - j_end)%2 != 0:
        print("Impossible")
        return
    elif abs(i_start - i_end)%4 != 0 and abs(j_start - j_end)%2 == 0:
        print("Impossible")
        return
    
    if i_start == i_end and j_start == j_end:
        print(num)
        print(steps)
        return
    if i_start > i_end and j_start >= j_end:
        num += 1
        steps += "UL "
        printShortestPath(n, i_start - 2, j_start - 1, i_end, j_end, num, steps)
        return
    elif i_start > i_end:
        num += 1
        steps += "UR "
        printShortestPath(n, i_start - 2, j_start + 1, i_end, j_end, num, steps)
        return
    elif i_start == i_end and j_start < j_end:
        num += 1
        steps += "R "
        printShortestPath(n, i_start, j_start + 2, i_end, j_end, num, steps)
        return
    elif i_start < i_end and j_start <= j_end:
        num += 1
        steps += "LR "
        printShortestPath(n, i_start + 2, j_start + 1, i_end, j_end, num, steps)
        return
    elif i_start < i_end and j_start > j_end:
        num += 1
        steps += "LL "
        printShortestPath(n, i_start + 2, j_start - 1, i_end, j_end, num, steps)
        return
    else:
        num += 1
        steps += "L "
        printShortestPath(n, i_start, j_start - 2, i_end, j_end, num, steps)
        return
    #  Print the distance along with the sequence of moves.

if __name__ == "__main__":
    n = int(input().strip())
    i_start, j_start, i_end, j_end = [int(x) for x in input().strip().split(' ')]
    num = 0
    steps = ""
    printShortestPath(n, i_start, j_start, i_end, j_end, num, steps)