import java.util.Scanner;

public class Main{

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);

		char [] a = sc.next().toCharArray();
		int b = 0;
		int c = 0;
		
		for(int i = 0; i <= a.length-1; i+=2) {
			if(a[i]=='L'){//奇数の条件
				System.out.println("No");
				System.exit(0);
			}
		}
		
		for(int j = 1; j <= a.length-1; j+=2) {
			if(a[j]=='R') { //偶数の条件
				System.out.println("No");
				System.exit(0);
			}
		}
		System.out.println("Yes");
	}
}
			
		









/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