"use strict"

function Main(input) {
  input = input.trim().split('');

  let N = input.length;
  let even = [];
  let odd = [];
  for(let i=0; i<N; i++){
    if((i+1)%2 === 0) {
      even.push(input[i]);
    } else {
      odd.push(input[i]);
    }
  }
  
  let ret = 'Yes';
  if(even.indexOf('R') !== -1) ret = 'No';
  if(odd.indexOf('L') !== -1) ret = 'No';

  console.log(ret);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));