#include<iostream>
using namespace std;
int main()
{
  string s;
  cin>>s;
  for(int i=0;i<s.size();i++)
  {
    if((i%2==0)&&(s[i]=='L')) {cout<<"No";return 0;}
    if((i%2==1)&&(s[i]=='R')) {cout<<"No"; return 0;}
                    }
        cout<<"Yes";
                    }

