let s = readLine()!

let a = Array(s.characters)
let evens: [Character] = ["R", "U", "D"]
let odds: [Character] = ["L", "U", "D"] 
var i = 0
var good = true

while i < a.count {
  if !evens.contains(a[i]) {
    good = false
    print("No")
    break
  }
  i += 2
}

i = 1 

while i < a.count && good {
  if !odds.contains(a[i]) {
    good = false
    print("No")
    break
  }
  i += 2
}

if good {
  print("Yes")
}