"use strict";
const Main = (input) =>{
   let xs = input.trim().split('');
   let list = [];
   for(let i = 0; i<xs.length; i++){
     list.push({
     xs: xs[i],
     index: i
     });    
    }
   let ans ="";
   for(let j = 0; j<xs.length; j++){
     if(list[j].index % j == 0){
       if(list[j].xs != "L"){
       ans ="Yes";
        }else{
       ans="No";
        }
     }
     if(list[j].index % j == 1){
       if(list[j].xs != "R"){
       ans ="Yes";
        }else{
       ans ="No";
        }
     } 
   }
  console.log(ans)
}
Main(require('fs').readFileSync('/dev/stdin','utf8'));