using System;
using System.Linq;
using System.Collections.Generic;
public class c
{
  public static void Main()
  {
      char[] RorB=Console.ReadLine().ToCharArray();
     int Rcount=0;
    for(int i=0;i<RorB.Length;i++)if(RorB[i]=='R')Rcount++;
     if(Rcount>RorB.Length-Rcount)Console.WriteLine("Yes");
     else Console.WriteLine("No");
  }
}