import java.util.Scanner;

public class a {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int m = in.nextInt();
        long field[][] = new long[n + 1][m + 1];
        long coin[][] = new long[n + 1][m + 1];
        for (int i = 0; i <= n; i++) {
            for (int j = 0; j <= m; j++) {
                coin[i][j] = Integer.MIN_VALUE;
            }
        }
        coin[1][0] = 0;
        coin[0][1] = 0;
        char rd[] = new char[m + n - 1];
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= m; j++) {
                field[i][j] = in.nextInt();
            }
        }
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= m; j++) {
                coin[i][j] = Math.max(coin[i - 1][j], coin[i][j - 1]) + field[i][j];
            }

        System.out.println(coin[n][m]);

        int a = n, b = m;
        for (int i = n + m - 2; i > 0; i--) {
            if (coin[a - 1][b] > coin[a][b - 1]) {
                rd[i] = 'D';
                a -= 1;
            } else {
                rd[i] = 'R';
                b -= 1;
            }
        }
        for (int i = 1; i < rd.length; i++) {
            System.out.print(rd[i]);
        }
    }
}