import java.util.Scanner;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    boolean result = true;
    char[] cs = sc.next().toCharArray();
    for (int i = 0; i < cs.length; i++)
      if (cs[i] == (i % 2 == 0 ? 'L' : 'R'))
        result = false;
    System.out.println(result ? "Yes" : "No");
  }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz