#include<iostream>
#include<algorithm>
using namespace std;

int main(){
	string S;
	cin >> S;
	
	for(int i=0;i<55;i++){
		if(S[2*i]=='L' || S[2*i+1]=='R'){
			cout << "No" << endl;
			return 0;
		}
	}
	cout << "Yes" << endl;
	
	return 0;
}