const main = (input) => {
  var s = input[0];
  var ans = true;
  s.split("").forEach((v,i)=>{
    if(i%2==0){
      if(['R', 'U', 'D'].indexOf(v) == -1) ans = false;
    }else{
      if(['L', 'U', 'D'].indexOf(v) == -1) ans = false;
    }
  })
  console.log(ans?"Yes":"No");
}
main(require('fs').readFileSync('/dev/stdin', 'UTF-8').trim().split("\n"));
