#include<iostream>
#include<algorithm>
#include<string>
#include<vector>
using namespace std;
int main(void)
{
    string s;
    cin>>s;
    int size;
    size_t size =s.length();
    int r;
    size/2<count(s.cbegin(),s.cend(),'R'?&"Yes":"No"
}