#!/bin/python

import sys

def printShortestPath(n, i_start, j_start, i_end, j_end):
    j = abs(i_start - i_end)
    i = abs(j_start - j_end)
    
    if j%2 != 0 or (i - (j/2))%2 != 0:
        print "Impossible"
        return
    
    up = 'U' if (j_start > j_end) else 'L'
    
    if(i == 0):
        side = 'R' if (up == 'L') else 'L'
        num = j/2
        mov = (up+ side +' ')*(j/4) + (up+ ('R' if side == 'L' else 'L') +' ')*(j/4)
    else:
        side = 'R' if (i_start < i_end) else 'L'
        mov = ''
        num = (j/2) + ((i - (j/2))/2)
        if up == 'U':
            mov += (up+ side +' ')*(j/2)
        if side == 'R':
            mov += (side + ' ')*((i - (j/2))/2)
        if up == 'L':
            mov += (up+ side +' ')*(j/2)
        if side == 'L':
            mov += (side + ' ')*((i - (j/2))/2)
            
    print num
    print mov

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)