s = gets.chomp

flag = 1
s.length.times do|i|
  if (i%2)==0 then
    if !(s[i]=='R'||s[i]=='U'||s[i]=='D') then
      flag = 0
      break
    end
  else 
    if !(s[i]=='L'||s[i]=='U'||s[i]=='D') then
      flag = 0
      break
    end
  end 
end
if flag ==1 then
  puts "Yes"
else 
  puts "No"
end