#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

void printShortestPath(int n, int is, int js, int ie, int je) {
    int count=0;
    char ans[10000009];
    int x=0;
    if((is%2==ie%2) && ((is%4==ie%4 && js%2==je%2) || (is%4!=ie%4 && js%2!=je%2)))
    {
    while(je!=js || ie!=is)
    {
        //UL, UR, R, LR, LL, L
        if(je>=js+1 && ie<=is-2)
        {
            ans[x]='U';
            ans[x+1]='R';
            ans[x+2]=' ';
            x+=3;
            //printf("UR ");
            js+=1;
            is-=2;
        }
        else if(ie<=is-2)
        {
            ans[x]='U';
            ans[x+1]='L';
            ans[x+2]=' ';
            x+=3;
            //printf("UL ");
            js-=1;
            is-=2;
        }
        else if(ie==is && je>=js+2)
        {
            ans[x]='R';
            ans[x+1]=' ';
            x+=2;
            //printf("R ");
            js+=2;
        }
        else if(ie>=is+2 && je<=js-1)
        {
            ans[x]='L';
            ans[x+1]='L';
            ans[x+2]=' ';
            x+=3;
            //printf("LL ");
            js-=1;
            is+=2;
        }
        else if(ie>=is+2)
        {
            ans[x]='L';
            ans[x+1]='R';
            ans[x+2]=' ';
            x+=3;
            //printf("LR ");
            js+=1;
            is+=2;
        }
        else if(ie==is && je<=js-2)
        {
            ans[x]='L';
            ans[x+1]=' ';
            x+=2;
            //printf("L ");
            js-=2;
        }
        count++;
        /*
        else
        {
            printf("______\n%d %d %d %d\n_______",is,js,ie,je);
            is=ie;
            js=je;
        }
        */
    }
        ans[x-1]='\0';
        printf("%d\n%s",count,ans);
    }
    else
    {
        printf("Impossible");
    }
        return;
    //  Print the distance along with the sequence of moves.
}

int main() {
    int n; 
    scanf("%i", &n);
    int i_start; 
    int j_start; 
    int i_end; 
    int j_end; 
    scanf("%i %i %i %i", &i_start, &j_start, &i_end, &j_end);
    printShortestPath(n, i_start, j_start, i_end, j_end);
    return 0;
}