from sys import stdin, stdout
# from math import sqrt, pi, acos, gcd, atan2, cos, sin, factorial, log10
# # from matplotlib import mlab
# # from matplotlib import pylab
# # from decimal import Decimal
# # from random import randint
# # import re
# PEPS = 1e-10
# INF = float('inf')
#
#
# def sqr(a):
#     return a * a
#
#
# def dist(a, b = (0, 0)):
#     return sqrt(sqr(a[0] - b[0]) + sqr(a[1] - b[1]))
#
#
# def s_dist(a, b = (0, 0)):
#     return (sqr(a[0] - b[0]) + sqr(a[1] - b[1]))
#
#
# def dist3(a, b = (0, 0, 0)):
#     return sqrt(sqr(a[0] - b[0]) + sqr(a[1] - b[1]) + sqr(a[2] - b[2]))
#
#
# def s_dist3(a, b = (0, 0, 0)):
#     return (sqr(a[0] - b[0]) + sqr(a[1] - b[1]) + sqr(a[2] - b[2]))
#
#
# def trans(p, al):
#     return (p[0] * cos(al) + p[1] * sin(al), - p[0] * sin(al) + p[1] * cos(al))
#
#
# def get_angle(a, b, c):
#     cos_al = (sqr(a) + sqr(b) - sqr(c)) / (2 * a * b)
#     return acos(cos_al)
#
#
# def write_float(ans):
#     stdout.write(str('%.13f' % ans) + '\n')
#
#
# def get_hight(pt1, pt2, pt3):
#     a = (pt2[0] - pt1[0], pt2[1] - pt1[1])
#     b = (pt3[0] - pt1[0], pt3[1] - pt1[1])
#     return abs(a[0] * b[1] - a[1] * b[0]) / dist(pt1, pt2)
#
#
# def get_square(pt1, pt2, pt3):
#     a = (pt2[0] - pt1[0], pt2[1] - pt1[1])
#     b = (pt3[0] - pt2[0], pt3[1] - pt2[1])
#     return (a[0] * b[-1] - a[1] * b[0]) / 2
#
#
# def sign(v):
#     if v > 0:
#         return 1
#     elif v < 0:
#         return -1
#     else:
#         return 0
#
#
# def inn(pt, triangle):
#     signs = set()
#     signs.add(sign(get_square(triangle[0], triangle[1], pt)))
#     signs.add(sign(get_square(triangle[1], triangle[2], pt)))
#     signs.add(sign(get_square(triangle[2], triangle[0], pt)))
#     return len(signs) == 1
#
#
# def inter_in(a, b):
#     return dist((a[0], a[1]), (b[0], b[1])) < a[-1] + b[-1]
#
#
# def inter_in3(a, b):
#     return dist3(a[:-1], b[:-1]) < a[-1] + b[-1]
#
#
# def shift(what, wth):
#     return (what[0] - wth[0], what[1] - wth[1])
#

s = stdin.readline().strip()
stdout.write(['No', 'Yes'][s.count('R') > s.count('B')])