#include<bits/stdc++.h>
using namespace std;
string s;
int main(){
int ind=0;
cin>>s;
for(int k=0;k<s.size();k++){
   if(s[k]=='L' && k%2==0)
        ind=1;
   if(s[k]=='R' && k%2==1)
    ind=1;
}
if(!ind)
    cout<<"Yes";
        else cout<<"No";

return 0;
}