import java.util.*;

public class Main {
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    String s = sc.next();
    char[] c = s.toCharArray();
    boolean t = true;
    for(int i=0;i<s.length();i++){
      if (i%2 == 0 && c[i] == 'L'){
        t = false;
        break;
      } else if (i%2 == 1 && c[i] == 'R'){
        t = false;
        break;
      }
    }
    if(t == true){
      System.out.println("Yes");
    } else if (t == false){
      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