#include <bits/stdc++.h>

using namespace std;

void printShortestPath(int n, int i_start, int j_start, int i_end, int j_end) {
    //  Print the distance along with the sequence of moves.
    int dr,dc,ans=0,z=0,imp=0;
    char x,y,str[20];
    dr=abs(i_start-i_end);
    dc=abs(j_start-j_end);
    if(dr==0 && dc==0) cout<<'0';
    /*if(i_start-i_end<0) x='L';
    else x='U';
    if(j_start-j_end<0) y='R';
    else y='L';*/
    while(dr>0 || dc>0){
        if(i_start-i_end<0) x='L';
        else x='U';
        if(j_start-j_end<0) y='R';
        else y='L';
        if(dc==0){
            if(dr%4==0){
                    str[z]=x;z++;y='R';
                    str[z]=y;z++;
                    str[z]=' ';z++;
                    ans++;
                    dr=dr-2;
                    i_start=abs(i_start-dr);
                    dc++;
                    j_start=abs(j_start+dc);
            }
             else{ cout<<"Impossible"; dr=0;dc=0;imp=1;}
        
        }
        else if(dr==0){
            if(dc%2==0){
                    str[z]=y;z++;
                    ans++;
                    dc=dc-2;
                    j_start=abs(dc-j_start);
            }
          else{ cout<<"Impossible"; dr=0;dc=0;imp=1;}
           
        }
        else if(dr>=2 && dc>=0){
            dr=dr-2;
            dc=dc-1;
            i_start=abs(dr-i_start);
            j_start=abs(dc-j_start);
            str[z]=x;z++;
            str[z]=y;z++;
            str[z]=' ';z++;
            ans++;
        }
        else{ cout<<"Impossible"; dr=0;dc=0;imp=1;}
    }
    if(imp==0){
    cout<<ans<<"\n";
    for(int i=0;i<z;i++) cout<<str[i];
     }
}

int main() {
    int n;
    cin >> n;
    int i_start;
    int j_start;
    int i_end;
    int j_end;
    cin >> i_start >> j_start >> i_end >> j_end;
    printShortestPath(n, i_start, j_start, i_end, j_end);
    return 0;
}