#include <iostream>
using namespace std;
int main()
{
	string s;
	getline(cin,s);
	int r_total=0,b_total=0;
	for (int i=0;i<=s.size()-1;i++)
	{
		if (s[i]=="B")  b_total++;
		else if (s[i]=="R")  r_total++;
	}
	if (b_total>r_total)  cout<<"Yes"<<endl;
	else cout<<"No"<<endl;
	return 0;
}