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

vector<string> v;
long int cn=0;
void func1(int x1, int y1, int x2, int y2){
    if(x1==x2 && y1==y2){
        return;
    }
    cn++;
    if(x2<x1){
        if(y2==y1){
            x1-=2;
            //cout<<"L ";
            v.push_back("L ");
        }
        else if(y2>y1){
            x1--;
            y1+=2;
            //cout<<"LL ";
            v.push_back("LL ");
        }
        else if(y2<y1){
            x1--;
            y1-=2;
            //cout<<"UL ";
            v.push_back("UL ");
        }
    }
    else if(x2==x1){
        if(y2>y1){
            x1++;
            y1+=2;
            //cout<<"LR ";
            v.push_back("LR ");
        }
        else if(y2<y1){
            x1--;
            y1-=2;
            //cout<<"UL ";
            v.push_back("UL ");
        }
    }
    else if(x2>x1){
        if(y2==y1){
            x1+=2;
            //cout<<"R ";
            v.push_back("R ");
        }
        else if(y2>y1){
            x1++;
            y1+=2;
            //cout<<"LR ";
            v.push_back("LR ");
        }
        else if(y2<y1){
            x1++;
            y1-=2;
            //cout<<"UR ";
            v.push_back("UR ");
        }
    }
    func1(x1,y1,x2,y2);
}

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int n;
    cin>>n;
    int x1,y1,x2,y2;
    cin>>y1>>x1>>y2>>x2;
    if((abs(y2-y1))%2==1){
        cout<<"Impossible";
        return 0;
    }
    if((abs(y2-y1))%4==0 && (abs(x2-x1))%2==1){
        cout<<"Impossible";
        return 0;
    }
    if((abs(y2-y1))%4!=0 && (abs(x2-x1))%2==0){
        cout<<"Impossible";
        return 0;
    }
    func1(x1,y1,x2,y2);
    int sz=v.size();
    cout<<cn<<endl;
    for(int i=0; i<sz; i++){
        cout<<v[i];
    }
    return 0;
}