#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp> // Common file
//#include <ext/pb_ds/tree_policy.hpp> // Including seg_tree_order_statistics_node_update
#include <stdio.h>
#include <cassert>
using namespace std;
//using namespace __gnu_pbds;
typedef long long lo;
typedef pair<lo,lo> ll;//pair
typedef vector<lo> vl;  //vector of long
typedef vector<ll > vll;   //vector of pair
typedef priority_queue<lo>p_q;
typedef vector< vl > vvl;  //vector of vectors
#define X first
#define Y second
#define mp(a,b) make_pair((a),(b))
#define REP(a,b) for(lo i=(a);i<(lo)b;i++)//no need to declare variable i
#define REPE(a,b,c,d) REP(a,b)for(lo j=(c);j<(lo)d;j++)//no need to declare vaiables i,j
#define REPV(a,b,c) for(lo(a)=b;(a)<(c);(a)++)//a is the variable
#define IREP(a,b) for(lo i=(a);i>=(b);i--)
#define IREPV(a,b,c) for(lo(a)=b;(a)>=(c);(a)--)
#define all(v) (v).begin(),(v).end()
#define TRV(a) for(auto it : a)
#define INF 500
#define MOD 1000000007
#define M 1000000007
#define CHECK_BIT(var,pos) ((var) & (1<<(pos)))
#define pb(a) push_back((a))
#define endl "\n"
#define eps 1e-9
#define PI 3.141592653589793
template<typename T> ostream& operator<< ( ostream &o,vector<T> v ) {
    if ( v.size() >0 )o<<v[0];
    for ( unsigned   i=1; i<v.size(); i++ )o<<" "<<v[i];
    return o<<endl;
}
template<typename U,typename V> ostream& operator<< ( ostream &o,pair<U,V> p ) {
    return o<<"("<<p.first<<", "<<p.second<<") ";
}
template<typename T> istream& operator>> ( istream &in,vector<T> &v ) {
    for ( unsigned   i=0; i<v.size(); i++ )in>>v[i];
    return in;
}
template<typename T> istream& operator>> ( istream &in,pair <T,T> &p ) {
    in>>p.X;
    in>>p.Y;
    return in;
}
#define debug(x) cout<<#x<<"="<<x<<endl;
vl dy={-1,1,2,1,-1,-2};
vl dx={-2,-2,0,2,2,0};
vector<string> an={"UL", "UR", "R", "LR", "LL", "L"};
vvl visited(INF,vl(INF,-1));
lo n;
void bfs(ll s){
    queue<ll>q;
    q.push(s);
    visited[s.X][s.Y]=0;
    while(!q.empty()){
        lo x=q.front().X;
        lo y=q.front().Y;
        q.pop();
        REP(0,6){
            lo nx=dx[i]+x;
            lo ny=dy[i]+y;
            if(nx>=0 and nx<n and ny>=0 and ny<n and visited [nx][ny]==-1){
                visited[nx][ny]=i;
                q.push(mp(nx,ny));
            }
        }
    }
}
int main(){
    std::ios::sync_with_stdio(false);
	cin.tie(0);cout.tie(0);cout.precision(20);
    cin>>n;
    ll s;
    cin>>s;
    bfs(s);
    lo x,y;
    cin>>x>>y;
    //REPE(0,n,0,n){cout<<visited[i][j]<<" ";if(j==n-1)cout<<endl;}
    if(visited[x][y]==-1){
        cout<<"Impossible";
    }
    else {
        lo res=0;
        vector<string>ans;
        ll en=mp(x,y);
        while(en!=s){
            ans.pb(an[visited[en.X][en.Y]]);
            x=en.X;
            y=en.Y;
            en.X-=dx[visited[x][y]];
            en.Y-=dy[visited[x][y]];
            res++;
        }
        reverse(all(ans));
        cout<<res<<endl;
        cout<<ans;
    }
    return 0;
}