s = gets.chomp.split("")
a = s.length
x = []
y = []
for num in 0..a-1 do
  if num.even?
    x << s[num]
  else
    y << s[num]
  end
end
if x.include?("L") || y.include?("R")
  puts "No"
else
  puts "Yes"
end