import java.util.*;

class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String s = sc.next();
    String[] str = s.split("");
    int length = str.length;
    
    boolean easiness = true;
    for(int i=0;i<length;i+=2) {
      if(str[i].equals("L")) {
        easiness = false;
        break;
      }
    }
    for(int i=1;i<length;i+=2) {
      if(str[i].equals("R")) {
        easiness = false;
        break;
      }
    }
    
    if(easiness) {
      System.out.println("Yes");
    }
    else {
      System.out.println("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