function Main(input){
  var S = input.split("");
  var jud;
  for(i=0;i<S.length;i++){
    if(i%2===1){
      if(S[i]==="L"||S[i]==="U"||S[i]==="D"){
        jud = true;
      }else{
        jud = false;
        console.log("No");
        break;
      }
    }else{
      if(S[i]==="R"||S[i]==="U"||S[i]==="D"){
        jud = true;
      }else{
        jud = false;
        console.log("No");
        break;
      }
    }
  }
  if(jud===true){
    console.log("Yes");
  }
}
 
Main(require("fs").readFileSync("/dev/stdin", "utf8"));


