#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    int n;
    cin>>n;
    int count=0,count1=0,count2=0,count3=0,count4=0;
    int is,js,ie,je;
    cin>>is>>js>>ie>>je;
    if((is-ie)%2!=0)
        cout<<"Impossible";
    else {
    while(is!=ie&&js!=je){
        while(is!=ie){
            if(is>ie&&js<je){
            is=is-2;
            js=js+1;
            count1++;
            //cout<<"UR";
            }
            else if (is>ie&&js>je){
            is=is-2;
            js=js-1;
            count2++;
            //cout<<"UL";
            }
            else if (is<ie&&js>je){
            is=is+2;
            js=js-1;
            count3++;
            //cout<<"LL";
            }
            else if (is<ie&&js<je){
            is=is+2;
            js=js+1;
            count4++;
            //cout<<"LR";
            }
        }
        if((js-je)%2==0){
            int x;
            x=(js-je)/2;
            //cout<<x;
            count=count1+count2+count3+count4;
            if(x>0)count=count+x;
            else count=count-x; 
            cout<<count<<endl; 
            for(int i=0;i<count1;i++)cout<<"UR"<<" " ;
            for(int i=0;i<count2;i++)cout<<"UL"<<" ";
            for(int i=0;i<count3;i++)cout<<"LL"<<" ";
            for(int i=0;i<count4;i++)cout<<"LR"<<" ";
            if(x>0) for(int i=0;i<x;i++)cout<<"L"<<" ";
            else for(int i=0;i<x;i++)cout<<"R"<<" ";
        }
        else cout<<"Impossible"; 
    }
    }
    
    
    
    return 0;
}