process.stdin.resume();
process.stdin.setEncoding('ascii');

var input_stdin = "";
var input_stdin_array = "";
var input_currentline = 0;

process.stdin.on('data', function (data) {
    input_stdin += data;
});

process.stdin.on('end', function () {
    input_stdin_array = input_stdin.split("\n");
    main();    
});

function readLine() {
    return input_stdin_array[input_currentline++];
}

/////////////// ignore above this line ////////////////////

var result = [];

function printShortestPath(n, i_start, j_start, i_end, j_end) {
    //  Print the distance along with the sequence of moves.
    if(i_start > n || j_start > n || i_start < 0 || j_start < 0 || i_end > n || j_end > n || i_end < 0 || j_end < 0){
        //Impossible
        result.push("Impossible");
        return;
    }
    else if(i_start > i_end && j_start >= j_end){
        // UL
        result.push("UL");
        printShortestPath(n,i_start - 2,j_start - 1,i_end,j_end);
        return;
    }
    else if(i_start > i_end && j_start <= j_end){
       //UR
        result.push("UR");
        printShortestPath(n,i_start - 2,j_start + 1,i_end,j_end);
        return;
    }
    else if(i_start == i_end && j_start < j_end){
        //R
        result.push("R");
        printShortestPath(n,i_start,j_start + 2,i_end,j_end);
        return;
    }
    else if(i_start < i_end && j_start <= j_end){
           //LR
        result.push("LR");
        printShortestPath(n,i_start + 2,j_start + 1,i_end,j_end);
        return;
    }
    else if(i_start < i_end && j_start >= j_end){
        //LL
        result.push("LL");
        printShortestPath(n,i_start + 2,j_start - 1,i_end,j_end);
        return;
    }
    else if(i_start == i_end && j_start > j_end){
            //L
        result.push("L");
        printShortestPath(n,i_start,j_start - 2,i_end,j_end);
        return;
    }
    else if(i_start == i_end && j_start == j_end){
        //match
        return;
    }
    else{
        result.push("Impossible");
        //Impossible
        return;
    }
}

function main() {
    var n = parseInt(readLine());
    var i_start_temp = readLine().split(' ');
    var i_start = parseInt(i_start_temp[0]);
    var j_start = parseInt(i_start_temp[1]);
    var i_end = parseInt(i_start_temp[2]);
    var j_end = parseInt(i_start_temp[3]);
    printShortestPath(n, i_start, j_start, i_end, j_end);
    if(result.indexOf("Impossible") == -1){
        console.log(result.length);
        var s = "";
        for(var i = 0;i < result.length;i++){
            s += result[i] + " ";
        }
        console.log(s);
    }
    else{
        console.log("Impossible");
    }

}