using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
class Solution {

    static void printShortestPath(int n, int i_start, int j_start, int i_end, int j_end) {
        if (Math.Abs(i_start-i_end) % 2 != 0){
            Console.WriteLine("Impossible");
            
        } else if (((Math.Abs(i_start-i_end)/2) % 2 == 1 & (Math.Abs(j_start-j_end)) % 2 == 0)){
            Console.WriteLine("Impossible");
            
        } else if (((Math.Abs(i_start-i_end)/2) % 2 == 0 & (Math.Abs(j_start-j_end)) % 2 != 0)){
            Console.WriteLine("Impossible");
            
        } else {
            int di = Math.Abs(i_start - i_end);
            int dj = Math.Abs(j_start - j_end);
            int iMoves = di / 2;
            int jMoves = 0;
            if (dj > iMoves){
                jMoves = (dj - iMoves)/2;
            }
            int moves = iMoves + jMoves;
            Console.WriteLine(moves);
            for (int i = 0; i < iMoves; i++){
                if(i_start < i_end){
                    Console.Write("L");
                    i_start += 2;
                    if (j_start <= j_end){
                        Console.Write("R ");
                        j_start += 1;
                    } else {
                        Console.Write("L ");
                        j_start -= 1;
                    }
                } else {
                    Console.Write("U");
                    i_start -= 2;
                    if (j_start <= j_end){
                        Console.Write("R ");
                        j_start += 1;
                    } else {
                        Console.Write("L ");
                        j_start -= 1;
                    }
                }
            }
            for (int i = 0; i < jMoves; i++){
                if (j_start <= j_end){
                        Console.Write("R ");
                        j_start += 1;
                    } else {
                        Console.Write("L ");
                        j_start -= 1;
                    }
            }
        }
    }

    static void Main(String[] args) {
        int n = Convert.ToInt32(Console.ReadLine());
        string[] tokens_i_start = Console.ReadLine().Split(' ');
        int i_start = Convert.ToInt32(tokens_i_start[0]);
        int j_start = Convert.ToInt32(tokens_i_start[1]);
        int i_end = Convert.ToInt32(tokens_i_start[2]);
        int j_end = Convert.ToInt32(tokens_i_start[3]);
        printShortestPath(n, i_start, j_start, i_end, j_end);
    }
}