#include <bits/stdc++.h>

using namespace std;

void printShortestPath(int n, int i_start, int j_start, int i_end, int j_end) {
    if(abs(i_start-i_end)%2 != 0){
        printf("Impossible\n");
        return;
    }
    if(abs(abs(j_start-j_end)-abs(i_start-i_end)/2)%2 != 0){
        printf("Impossible\n");
        return;
    }
    int steps = abs(i_start-i_end)/2 + abs(abs(j_start-j_end)-abs(i_start-i_end)/2)/2;
    cout<<steps<<endl;
    if(i_end <= i_start){
        if(j_end <= j_start){
            for(int i=0; i<abs(i_start-i_end)/2; i++){
                cout<<"UL ";
            }
        }else{
            for(int i=0; i<abs(i_start-i_end)/2; i++){
                cout<<"UR ";
            }
        }
    }
}

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;
}