#include <bits/stdc++.h>
#include <sstream>

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 n_vertical = (i_start - i_end)/2;
    if ((i_start - i_end)%2 || (j_start - j_end - n_vertical)%2){
       cout << "Impossible" << endl;
       return;
    }
    int i_curr = i_start;
    int j_curr = j_start;
    int steps = 0;
    ostringstream oss;
    while(i_curr != i_end)
    {
        if (i_curr < i_end)
        {
            i_curr +=2;
            oss << "L";
            if (j_curr <= j_end){
                oss << "R";
                j_curr++;
            }else{
                oss << "L";
                j_curr--;
            }
        }else{  // i_curr > i_end
            i_curr -= 2;
            oss << "U";
            if (j_curr <= j_end){
                j_curr++;
                oss << "R";
            }else{
                oss << "L";
                j_curr--;
            }
        }
        oss << " ";
        steps++;
    }
    // now i_curr == i_start
    while(j_curr != j_end)
    {
        if (j_curr < j_end)
        {
            oss << "R";
            j_curr+=2;
        }else{
            oss << "L";
            j_curr-=2;
        }
        //cout << "Moving horizontally - i_curr = " << i_curr << "\tj_curr = " << j_curr << endl;
        steps++;
        oss << " ";
    }
    cout << steps << endl;
    cout << oss.str() << endl;

}

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;
}